{"id":362,"date":"2015-06-16T16:41:19","date_gmt":"2015-06-16T14:41:19","guid":{"rendered":"http:\/\/duch.mimuw.edu.pl\/~bojan\/podpunkt\/?page_id=362"},"modified":"2017-10-31T13:06:49","modified_gmt":"2017-10-31T12:06:49","slug":"generating-operations","status":"publish","type":"page","link":"https:\/\/www.mimuw.edu.pl\/~bojan\/20142015-2\/alg\/all-countable-chains-a-new-proof\/generating-operations","title":{"rendered":"Genarating operations"},"content":{"rendered":"<p>Let <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-571dff900a291078b942a8cfd0d1b4ee_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#92;&#97;&#108;&#103;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"11\" style=\"vertical-align: 0px;\"\/> be a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-32587f686fd9ec2fcf34e53285ce1dd5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#92;&#99;&#99;&#104;&#97;&#105;&#110;\" title=\"Rendered by QuickLaTeX.com\" height=\"7\" width=\"14\" style=\"vertical-align: 0px;\"\/>-algebra, and let <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-19b05d631b5bf57a37c7695615ec2b6b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"12\" style=\"vertical-align: 0px;\"\/> be a subset of its universe. The subset of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-571dff900a291078b942a8cfd0d1b4ee_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#92;&#97;&#108;&#103;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"11\" style=\"vertical-align: 0px;\"\/> generated by <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-19b05d631b5bf57a37c7695615ec2b6b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"12\" style=\"vertical-align: 0px;\"\/> is defined to be the least subset of the universe which contains <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-19b05d631b5bf57a37c7695615ec2b6b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"12\" style=\"vertical-align: 0px;\"\/> and is closed under the multiplication operation of the algebra. By associativity, this subset is the same thing as the image of the multiplication operation over the set <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-07e29dbe513df36e60f9142f4d77115a_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#92;&#99;&#99;&#104;&#97;&#105;&#110;&#32;&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"28\" style=\"vertical-align: 0px;\"\/>. The following theorem shows that the elements generated by <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-19b05d631b5bf57a37c7695615ec2b6b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"12\" style=\"vertical-align: 0px;\"\/> can be generated by using only the basic operations that were already used in the characterisation theorem from the <a title=\"10. All countable chains\" href=\"https:\/\/www.mimuw.edu.pl\/~bojan\/20142015-2\/alg\/all-countable-chains-a-new-proof\">parent\u00a0page<\/a>.<\/p>\n<p><strong>Theorem. <\/strong>Let <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-571dff900a291078b942a8cfd0d1b4ee_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#92;&#97;&#108;&#103;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"11\" style=\"vertical-align: 0px;\"\/> be a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-32587f686fd9ec2fcf34e53285ce1dd5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#92;&#99;&#99;&#104;&#97;&#105;&#110;\" title=\"Rendered by QuickLaTeX.com\" height=\"7\" width=\"14\" style=\"vertical-align: 0px;\"\/>-algebra with finite universe. For every subset <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-19b05d631b5bf57a37c7695615ec2b6b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"12\" style=\"vertical-align: 0px;\"\/> of the universe, the subset generated by <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-19b05d631b5bf57a37c7695615ec2b6b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"12\" style=\"vertical-align: 0px;\"\/> is the least subset that contains <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-19b05d631b5bf57a37c7695615ec2b6b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#66;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"12\" style=\"vertical-align: 0px;\"\/> and is closed under binary product, shuffle, as well as the powers <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-f2f0db3c7332040ce9ef8127dfa75ec5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#97;&#94;&#92;&#111;&#109;&#101;&#103;&#97;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"16\" style=\"vertical-align: 0px;\"\/> and \u00a0<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-content\/ql-cache\/quicklatex.com-e1b4a0ee57cd2ff676c7ac4dccbf21bb_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#97;&#94;&#123;&#45;&#92;&#111;&#109;&#101;&#103;&#97;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"25\" style=\"vertical-align: 0px;\"\/>.<\/p>\n<p>The proof of this theorem is similar to the one in the parent page.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Let be a -algebra, and let be a subset of its universe. The subset of generated by is defined to be the least subset of the universe which contains and is closed under the multiplication operation of the algebra. By associativity, this subset is the same thing as the image of the multiplication operation over [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1062,"menu_order":0,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"class_list":["post-362","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/pages\/362"}],"collection":[{"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/comments?post=362"}],"version-history":[{"count":5,"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/pages\/362\/revisions"}],"predecessor-version":[{"id":1411,"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/pages\/362\/revisions\/1411"}],"up":[{"embeddable":true,"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/pages\/1062"}],"wp:attachment":[{"href":"https:\/\/www.mimuw.edu.pl\/~bojan\/wp-json\/wp\/v2\/media?parent=362"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}