<?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 general)</title><link>https://jaalonso.github.io/calculemus/</link><description></description><atom:link href="https://jaalonso.github.io/calculemus/tags/interseccion-general.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; 
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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 "s ∪ (⋂_i A_i) = ⋂_i (A_i ∪ s)"</title><link>https://jaalonso.github.io/calculemus/posts/2021/06/04-union_con_interseccion_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.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;Union_con_interseccion_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;hr&gt;
&lt;p&gt;&lt;a href="https://jaalonso.github.io/calculemus/posts/2021/06/04-union_con_interseccion_general/"&gt;Leer más…&lt;/a&gt; (quedan 9 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><category>Conjuntos</category><category>Intersección general</category><category>Isabelle</category><category>Lean4</category><category>Unión</category><guid>https://jaalonso.github.io/calculemus/posts/2021/06/04-union_con_interseccion_general/</guid><pubDate>Fri, 04 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></channel></rss>