<?xml version="1.0" encoding="utf-8"?>
<?xml-stylesheet type="text/xsl" href="../assets/xml/rss.xsl" media="all"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Calculemus (Publicaciones sobre Intersección)</title><link>https://jaalonso.github.io/calculemus/</link><description></description><atom:link href="https://jaalonso.github.io/calculemus/tags/interseccion.xml" rel="self" type="application/rss+xml"></atom:link><language>es</language><copyright>Contents © 2026 &lt;a href="mailto:"&gt;José A. Alonso&lt;/a&gt; 
&lt;a rel="license" href="https://creativecommons.org/licenses/by-nc-sa/4.0/"&gt;
&lt;img alt="Creative Commons License BY-NC-SA"
style="border-width:0; margin-bottom:12px;"
src="https://i.creativecommons.org/l/by-nc-sa/4.0/88x31.png"&gt;&lt;/a&gt;</copyright><lastBuildDate>Sun, 18 Oct 2026 17:47:01 GMT</lastBuildDate><generator>Nikola (getnikola.com)</generator><docs>http://blogs.law.harvard.edu/tech/rss</docs><item><title>Demostraciones de "f⁻¹(u ∩ v) = f⁻¹(u) ∩ f⁻¹(v)"</title><link>https://jaalonso.github.io/calculemus/posts/2021/06/05-imagen_inversa_de_la_interseccion/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 y con Isabelle/HOL que&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="w"&gt;   &lt;/span&gt;&lt;span class="n"&gt;f&lt;/span&gt;&lt;span class="bp"&gt;⁻¹&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;v&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;f&lt;/span&gt;&lt;span class="bp"&gt;⁻¹&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;f&lt;/span&gt;&lt;span class="bp"&gt;⁻¹&lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;v&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Function&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;β&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kt"&gt;Type&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;_&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;f&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;→&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;β&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;v&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;β&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;f&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⁻¹'&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;v&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;f&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⁻¹'&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;f&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⁻¹'&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;v&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;y la siguiente teoría de Iasbelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Imagen_inversa_de_la_interseccion&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"f -` (u ∩ v) = f -` u ∩ f -` v"&lt;/span&gt;
&lt;span class="gr"&gt;sorry&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;hr&gt;
&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/06/05-imagen_inversa_de_la_interseccion/"&gt;Leer más…&lt;/a&gt; (quedan 7 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Funciones</category><category>Imagen inversa</category><category>Intersección</category><category>Isabelle</category><category>Lean4</category><guid>https://jaalonso.github.io/calculemus/posts/2021/06/05-imagen_inversa_de_la_interseccion/</guid><pubDate>Sat, 05 Jun 2021 04:00:00 GMT</pubDate></item><item><title>Demostraciones de "⋂_i, (A(i) ∩ B(i)) = (⋂_i, A(i)) ∩ (⋂_i, B(i))"</title><link>https://jaalonso.github.io/calculemus/posts/2021/06/03-interseccion_de_intersecciones/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 y con Isabelle/HOL que
\[ ⋂_i (A_i ∩ B_i) = (⋂_i A_i) ∩ (⋂_i B_i) \]&lt;/p&gt;
&lt;p&gt;Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Basic&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Tactic&lt;/span&gt;

&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;

&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kt"&gt;Type&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;A&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;B&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;ℕ&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;→&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="bp"&gt;⋂&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;,&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;A&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;B&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="bp"&gt;⋂&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;,&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;A&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="bp"&gt;⋂&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;,&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;B&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;la siguiente teoría de Isabelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Interseccion_de_intersecciones&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"(⋂ i ∈ I. A i ∩ B i) = (⋂ i ∈ I. A i) ∩ (⋂ i ∈ I. B i)"&lt;/span&gt;
&lt;span class="gr"&gt;sorry&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;hr&gt;
&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/06/03-interseccion_de_intersecciones/"&gt;Leer más…&lt;/a&gt; (quedan 7 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Intersección</category><category>Intersección general</category><category>Isabelle</category><category>Lean4</category><guid>https://jaalonso.github.io/calculemus/posts/2021/06/03-interseccion_de_intersecciones/</guid><pubDate>Thu, 03 Jun 2021 04:00:00 GMT</pubDate></item><item><title>Demostraciones de "s ∩ ⋃_i A_i = ⋃_i (A_i ∩ s)"</title><link>https://jaalonso.github.io/calculemus/posts/2021/06/02-distributiva_de_la_interseccion_respecto_de_la_union_general/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 y con Isabelle/HOL que
\[ s ∩ ⋃_i A_i = ⋃_i (A_i ∩ s) \]&lt;/p&gt;
&lt;p&gt;Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Basic&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Lattice&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Tactic&lt;/span&gt;

&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;

&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kt"&gt;Type&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;A&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;ℕ&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;→&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="bp"&gt;⋃&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;,&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;A&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⋃&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="o"&gt;,&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;A&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;i&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;y la siguiente teoría de Isabelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Distributiva_de_la_interseccion_respecto_de_la_union_general&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"s ∩ (⋃ i ∈ I. A i) = (⋃ i ∈ I. (A i ∩ s))"&lt;/span&gt;
&lt;span class="gr"&gt;sorry&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/06/02-distributiva_de_la_interseccion_respecto_de_la_union_general/"&gt;Leer más…&lt;/a&gt; (quedan 7 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Intersección</category><category>Isabelle</category><category>Lean4</category><category>Unión general</category><guid>https://jaalonso.github.io/calculemus/posts/2021/06/02-distributiva_de_la_interseccion_respecto_de_la_union_general/</guid><pubDate>Wed, 02 Jun 2021 04:00:00 GMT</pubDate></item><item><title>Los primos mayores que 2 son impares</title><link>https://jaalonso.github.io/calculemus/posts/2021/06/01-interseccion_de_los_primos_y_los_mayores_que_dos/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 y con Isabelle/HOL que los primos mayores que 2 son impares. Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Algebra.Ring.Parity&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Tactic&lt;/span&gt;

&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Nat&lt;/span&gt;

&lt;span class="kd"&gt;def&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Primos&lt;/span&gt;&lt;span class="w"&gt;      &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;ℕ&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;n&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;|&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Nat.Prime&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;n&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;def&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;MayoresQue2&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;ℕ&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;n&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;|&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;n&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;&amp;gt;&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="mi"&gt;2&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;def&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Impares&lt;/span&gt;&lt;span class="w"&gt;     &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;ℕ&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;n&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;|&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;¬&lt;/span&gt;&lt;span class="n"&gt;Even&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;n&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Primos&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;MayoresQue2&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⊆&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Impares&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;y la siguiente teoría de Isabelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Interseccion_de_los_primos_y_los_mayores_que_dos&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"HOL-Number_Theory.Number_Theory"&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="k"&gt;definition&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;primos&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;::&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"nat set"&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kp"&gt;where&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="s"&gt;"primos = {n ∈ ℕ . prime n}"&lt;/span&gt;

&lt;span class="k"&gt;definition&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;mayoresQue2&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;::&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"nat set"&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kp"&gt;where&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="s"&gt;"mayoresQue2 = {n ∈ ℕ . n &amp;gt; 2}"&lt;/span&gt;

&lt;span class="k"&gt;definition&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;impares&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;::&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"nat set"&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kp"&gt;where&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="s"&gt;"impares = {n ∈ ℕ . ¬ even n}"&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"primos ∩ mayoresQue2 ⊆ impares"&lt;/span&gt;
&lt;span class="gr"&gt;oops&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/06/01-interseccion_de_los_primos_y_los_mayores_que_dos/"&gt;Leer más…&lt;/a&gt; (quedan 3 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Inclusión</category><category>Intersección</category><category>Isabelle</category><category>Lean4</category><guid>https://jaalonso.github.io/calculemus/posts/2021/06/01-interseccion_de_los_primos_y_los_mayores_que_dos/</guid><pubDate>Tue, 01 Jun 2021 04:00:00 GMT</pubDate></item><item><title>Demostraciones de "(s \ t) ∪ (t \ s) = (s ∪ t) \ (s ∩ t)"</title><link>https://jaalonso.github.io/calculemus/posts/2021/05/28-diferencia_de_union_e_interseccion/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 y con Isabelle/HOL que
\[ (s \setminus t) ∪ (t \setminus s) = (s ∪ t) \setminus (s ∩ t) \]&lt;/p&gt;
&lt;p&gt;Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Basic&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Tactic&lt;/span&gt;

&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;

&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kt"&gt;Type&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;\\&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∪&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;\\&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;=&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∪&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;\\&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;y la siguiente teoría de Isabelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Diferencia_de_union_e_interseccion&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"(s - t) ∪ (t - s) = (s ∪ t) - (s ∩ t)"&lt;/span&gt;
&lt;span class="gr"&gt;oops&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;hr&gt;
&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/05/28-diferencia_de_union_e_interseccion/"&gt;Leer más…&lt;/a&gt; (quedan 14 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Diferencia</category><category>Intersección</category><category>Isabelle</category><category>Lean4</category><category>Unión</category><guid>https://jaalonso.github.io/calculemus/posts/2021/05/28-diferencia_de_union_e_interseccion/</guid><pubDate>Fri, 28 May 2021 04:00:00 GMT</pubDate></item><item><title>Demostraciones de "(s ∩ t) ∪ (s ∩ u) ⊆ s ∩ (t ∪ u)"</title><link>https://jaalonso.github.io/calculemus/posts/2021/05/20-propiedad_semidistributiva_de_la_interseccion_sobre_la_union_2/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 y con Isabelle/HOL que
\[ (s ∩ t) ∪ (s ∩ u) ⊆ s ∩ (t ∪ u) \]&lt;/p&gt;
&lt;p&gt;Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Basic&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Tactic&lt;/span&gt;

&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;

&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kt"&gt;Type&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∪&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⊆&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∪&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="o"&gt;):=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;y la siguiente teoría de Isabelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Propiedad_semidistributiva_de_la_interseccion_sobre_la_union_2&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"(s ∩ t) ∪ (s ∩ u) ⊆ s ∩ (t ∪ u)"&lt;/span&gt;
&lt;span class="gr"&gt;oops&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;hr&gt;
&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/05/20-propiedad_semidistributiva_de_la_interseccion_sobre_la_union_2/"&gt;Leer más…&lt;/a&gt; (quedan 4 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Inclusióm</category><category>Intersección</category><category>Isabelle</category><category>Lean4</category><category>Unión</category><guid>https://jaalonso.github.io/calculemus/posts/2021/05/20-propiedad_semidistributiva_de_la_interseccion_sobre_la_union_2/</guid><pubDate>Thu, 20 May 2021 04:00:00 GMT</pubDate></item><item><title>Demostraciones de "s ∩ (t ∪ u) ⊆ (s ∩ t) ∪ (s ∩ u)"</title><link>https://jaalonso.github.io/calculemus/posts/2021/05/18-propiedad_semidistributiva_de_la_interseccion_sobre_la_union/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 y con Isabelle/HOL que
\[s ∩ (t ∪ u) ⊆ (s ∩ t) ∪ (s ∩ u)\]&lt;/p&gt;
&lt;p&gt;Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Basic&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Tactic&lt;/span&gt;
&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kt"&gt;Type&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∪&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⊆&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∪&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;y la siguiente teoría de Isabelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Propiedad_semidistributiva_de_la_interseccion_sobre_la_union&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"s ∩ (t ∪ u) ⊆ (s ∩ t) ∪ (s ∩ u)"&lt;/span&gt;
&lt;span class="gr"&gt;oops&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;hr&gt;
&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/05/18-propiedad_semidistributiva_de_la_interseccion_sobre_la_union/"&gt;Leer más…&lt;/a&gt; (quedan 5 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Inclusióm</category><category>Intersección</category><category>Isabelle</category><category>Lean4</category><category>Unión</category><guid>https://jaalonso.github.io/calculemus/posts/2021/05/18-propiedad_semidistributiva_de_la_interseccion_sobre_la_union/</guid><pubDate>Tue, 18 May 2021 04:00:00 GMT</pubDate></item><item><title>Demostraciones de "Si s ⊆ t, entonces s ∩ u ⊆ t ∩ u"</title><link>https://jaalonso.github.io/calculemus/posts/2021/05/17-propiedad_de_monotonia_de_la_interseccion/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Demostrar con Lean4 e Isabelle/HOL que&lt;/p&gt;
&lt;blockquote&gt;
&lt;p&gt;Si \(s ⊆ t\), entonces \(s ∩ u ⊆ t ∩ u\).&lt;/p&gt;
&lt;/blockquote&gt;
&lt;p&gt;Para ello, completar la siguiente teoría de Lean4:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Data.Set.Basic&lt;/span&gt;
&lt;span class="kn"&gt;import&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Mathlib.Tactic&lt;/span&gt;
&lt;span class="kn"&gt;open&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;{&lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="kt"&gt;Type&lt;/span&gt;&lt;span class="o"&gt;}&lt;/span&gt;
&lt;span class="kd"&gt;variable&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Set&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;α&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;

&lt;span class="kd"&gt;example&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="o"&gt;(&lt;/span&gt;&lt;span class="n"&gt;h&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⊆&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="o"&gt;)&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="o"&gt;:&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;s&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;⊆&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;t&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="bp"&gt;∩&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;u&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="o"&gt;:=&lt;/span&gt;
&lt;span class="kd"&gt;by&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="gr"&gt;sorry&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;p&gt;y la siguiente teoría de Isabelle/HOL:&lt;/p&gt;
&lt;div class="code"&gt;&lt;pre class="code literal-block"&gt;&lt;span class="k"&gt;theory&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Propiedad_de_monotonia_de_la_interseccion&lt;/span&gt;
&lt;span class="kp"&gt;imports&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="n"&gt;Main&lt;/span&gt;
&lt;span class="k"&gt;begin&lt;/span&gt;

&lt;span class="kn"&gt;lemma&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="kp"&gt;assumes&lt;/span&gt;&lt;span class="w"&gt; &lt;/span&gt;&lt;span class="s"&gt;"s ⊆ t"&lt;/span&gt;
&lt;span class="w"&gt;  &lt;/span&gt;&lt;span class="kp"&gt;shows&lt;/span&gt;&lt;span class="w"&gt;   &lt;/span&gt;&lt;span class="s"&gt;"s ∩ u ⊆ t ∩ u"&lt;/span&gt;
&lt;span class="gr"&gt;oops&lt;/span&gt;

&lt;span class="k"&gt;end&lt;/span&gt;
&lt;/pre&gt;&lt;/div&gt;

&lt;hr&gt;
&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/05/17-propiedad_de_monotonia_de_la_interseccion/"&gt;Leer más…&lt;/a&gt; (quedan 3 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Inclusióm</category><category>Intersección</category><category>Isabelle</category><category>Lean4</category><category>Unión</category><guid>https://jaalonso.github.io/calculemus/posts/2021/05/17-propiedad_de_monotonia_de_la_interseccion/</guid><pubDate>Mon, 17 May 2021 04:00:00 GMT</pubDate></item></channel></rss>