Superparticular ratio: Difference between revisions

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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
Superparticular numbers are ratios of the form (n+1)/n, or 1+1/n, where n is a whole number greater than 0. In ancient Greece they were known as Epimoric (επιμοριοσ, epimorios) ratios, which is literally translated as "above a part."
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The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
<h4>Original Wikitext content:</h4>
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;white-space: pre-wrap ! important" class="old-revision-html">Superparticular numbers are ratios of the form (n+1)/n, or 1+1/n, where n is a whole number greater than 0. In ancient Greece they were known as Epimoric (επιμοριοσ, epimorios) ratios, which is literally translated as "above a part."


These ratios have some peculiar properties:
These ratios have some peculiar properties:
* The difference tone of the dyad is also the virtual fundamental.
 
* The first 6 such ratios ([[3_2|3/2]], [[4_3|4/3]], [[5_4|5/4]], [[6_5|6/5]], [[7_6|7/6]], [[8_7|8/7]]) are notable [[harmonic entropy]] minima.
<ul><li>The difference tone of the dyad is also the virtual fundamental.</li><li>The first 6 such ratios ([[3/2|3/2]], [[4/3|4/3]], [[5/4|5/4]], [[6/5|6/5]], [[7/6|7/6]], [[8/7|8/7]]) are notable [[Harmonic_Entropy|harmonic entropy]] minima.</li><li>The difference (i.e. quotient) between two successive epimoric ratios is always an epimoric ratio.</li><li>The sum (i.e. product) of two successive epimoric ratios is either an epimoric ratio or an [[Superpartient|epimeric ratio]].</li><li>Every epimoric ratio can be split into the product of two epimoric ratios. One way is via the identity 1+1/n = (1+1/(2n))*(1+1/(2n+1)), but more than one such splitting method may exist.</li><li>If a/b and c/d are Farey neighbors, that is if a/b &lt; c/d and bc - ad = 1, then (c/d)/(a/b) = bc/ad is epimoric.</li></ul>
* The difference (i.e. quotient) between two successive epimoric ratios is always an epimoric ratio.
* The sum (i.e. product) of two successive epimoric ratios is either an epimoric ratio or an [[Superpartient|epimeric ratio]].
* Every epimoric ratio can be split into the product of two epimoric ratios. One way is via the identity 1+1/n = (1+1/(2n))*(1+1/(2n+1)), but more than one such splitting method may exist.
* If a/b and c/d are Farey neighbors, that is if a/b &lt; c/d and bc - ad = 1, then (c/d)/(a/b) = bc/ad is epimoric.


Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a [[Harmonic|multiple of the fundamental]] (the same rule applies to all natural harmonics in the Greek system).
Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a [[Harmonic|multiple of the fundamental]] (the same rule applies to all natural harmonics in the Greek system).


See: [[List of Superparticular Intervals]] and the Wikipedia page for [[http://en.wikipedia.org/wiki/Superparticular_number|Superparticular number]].</pre></div>
See: [[List_of_Superparticular_Intervals|List of Superparticular Intervals]] and the Wikipedia page for [http://en.wikipedia.org/wiki/Superparticular_number Superparticular number].
<h4>Original HTML content:</h4>
[[Category:epimoric]]
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;superparticular&lt;/title&gt;&lt;/head&gt;&lt;body&gt;Superparticular numbers are ratios of the form (n+1)/n, or 1+1/n, where n is a whole number greater than 0. In ancient Greece they were known as Epimoric (επιμοριοσ, epimorios) ratios, which is literally translated as &amp;quot;above a part.&amp;quot;&lt;br /&gt;
[[Category:greek]]
&lt;br /&gt;
[[Category:ratio]]
These ratios have some peculiar properties:&lt;br /&gt;
[[Category:superparticular]]
&lt;ul&gt;&lt;li&gt;The difference tone of the dyad is also the virtual fundamental.&lt;/li&gt;&lt;li&gt;The first 6 such ratios (&lt;a class="wiki_link" href="/3_2"&gt;3/2&lt;/a&gt;, &lt;a class="wiki_link" href="/4_3"&gt;4/3&lt;/a&gt;, &lt;a class="wiki_link" href="/5_4"&gt;5/4&lt;/a&gt;, &lt;a class="wiki_link" href="/6_5"&gt;6/5&lt;/a&gt;, &lt;a class="wiki_link" href="/7_6"&gt;7/6&lt;/a&gt;, &lt;a class="wiki_link" href="/8_7"&gt;8/7&lt;/a&gt;) are notable &lt;a class="wiki_link" href="/harmonic%20entropy"&gt;harmonic entropy&lt;/a&gt; minima.&lt;/li&gt;&lt;li&gt;The difference (i.e. quotient) between two successive epimoric ratios is always an epimoric ratio.&lt;/li&gt;&lt;li&gt;The sum (i.e. product) of two successive epimoric ratios is either an epimoric ratio or an &lt;a class="wiki_link" href="/Superpartient"&gt;epimeric ratio&lt;/a&gt;.&lt;/li&gt;&lt;li&gt;Every epimoric ratio can be split into the product of two epimoric ratios. One way is via the identity 1+1/n = (1+1/(2n))*(1+1/(2n+1)), but more than one such splitting method may exist.&lt;/li&gt;&lt;li&gt;If a/b and c/d are Farey neighbors, that is if a/b &amp;lt; c/d and bc - ad = 1, then (c/d)/(a/b) = bc/ad is epimoric.&lt;/li&gt;&lt;/ul&gt;&lt;br /&gt;
Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a &lt;a class="wiki_link" href="/Harmonic"&gt;multiple of the fundamental&lt;/a&gt; (the same rule applies to all natural harmonics in the Greek system).&lt;br /&gt;
&lt;br /&gt;
See: &lt;a class="wiki_link" href="/List%20of%20Superparticular%20Intervals"&gt;List of Superparticular Intervals&lt;/a&gt; and the Wikipedia page for &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Superparticular_number" rel="nofollow"&gt;Superparticular number&lt;/a&gt;.&lt;/body&gt;&lt;/html&gt;</pre></div>