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<?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 Relaciones)</title><link>https://jaalonso.github.io/calculemus/</link><description></description><atom:link href="https://jaalonso.github.io/calculemus/es/categories/cat_relaciones.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>Wed, 14 Oct 2026 18:49:44 GMT</lastBuildDate><generator>Nikola (getnikola.com)</generator><docs>http://blogs.law.harvard.edu/tech/rss</docs><item><title>Las relaciones reflexivas y circulares son simétricas</title><link>https://jaalonso.github.io/calculemus/es/posts/2020/04/08-las_reflexivas_circulares_son_simetricases/</link><dc:creator>José A. Alonso</dc:creator><description>&lt;div&gt;&lt;hr&gt;
&lt;p&gt;Se dice que la relación binaria \(R\) es&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;reflexiva si \((∀x)R(x, x)\)&lt;/li&gt;
&lt;li&gt;circular si \((∀x, y, z)[R(x, y) ∧ R(y, z) ⟶ R(z, x)]\)&lt;/li&gt;
&lt;li&gt;simétrica si \((∀x, y)[R(x, y) ⟶ R(y, x)]\)&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;Demostrar que las relaciones reflexivas y circulares son simétricas. Para ello, completar 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;Las_reflexivas_circulares_son_simetricas&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;"∀x. R(x, x)"&lt;/span&gt;
&lt;span class="w"&gt;          &lt;/span&gt;&lt;span class="s"&gt;"∀x y z. R(x, y) ∧ R(y, z) ⟶ R(z, x)"&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;"∀x y. R(x, y) ⟶ R(y, x)"&lt;/span&gt;
&lt;span class="w"&gt;  &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/es/posts/2020/04/08-las_reflexivas_circulares_son_simetricases/"&gt;Leer más…&lt;/a&gt; (quedan 1 minutos de lectura)&lt;/p&gt;&lt;/div&gt;</description><guid>https://jaalonso.github.io/calculemus/es/posts/2020/04/08-las_reflexivas_circulares_son_simetricases/</guid><pubDate>Wed, 08 Apr 2020 04:00:00 GMT</pubDate></item></channel></rss>