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  <id>9790</id>
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  <last_published>2013-01-16T13:00:10</last_published>
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&lt;mdoxml version=&quot;1.0&quot;&gt;Abhay sent us this investigation and discovery of some structural arithmetical patterns held by cyclic sets of natural numbers.&lt;br&gt;&lt;/br&gt;
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You can  &lt;a href=&quot;/content/id/9790/Theory%20of%20Cycles.pdf&quot;&gt;read about his theory of cycles here&lt;/a&gt;.&lt;br&gt;&lt;/br&gt;
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Can you follow Abhay&amp;#39;s argument? Does this fit into a larger structure about which you already know?  Perhaps you can suggest some generalisations?  &lt;br&gt;&lt;/br&gt;
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If you wish to comment on the investigation or discuss it with others, you can use &lt;a href=&quot;http://nrich.maths.org/discus/messages/27/154555.html&quot;&gt;this thread&lt;/a&gt; on the Ask NRICH forum&lt;br&gt;&lt;/br&gt;
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&lt;div class=&quot;framework&quot;&gt;This article was authored by V. Abhay Rangan studying in 10th standard, in Poorna Prajna Education Centre, Indiranagar, Bangalore, India.&lt;/div&gt;
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&lt;br&gt;&lt;/br&gt;&lt;/mdoxml&gt;</indexXML>
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  <title>Rangan's theory of cycles</title>
  <description>In this beautifully written-up investigation Abhay describes his discovery of a 'theory of cycles'.</description>
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