Superparticular ratio: Difference between revisions

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**Imported revision 244988153 - Original comment: **
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**Imported revision 244989655 - Original comment: **
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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
<h2>IMPORTED REVISION FROM WIKISPACES</h2>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2011-08-09 03:10:29 UTC</tt>.<br>
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2011-08-09 03:32:11 UTC</tt>.<br>
: The original revision id was <tt>244988153</tt>.<br>
: The original revision id was <tt>244989655</tt>.<br>
: The revision comment was: <tt></tt><br>
: The revision comment was: <tt></tt><br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
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* The difference (ie quotient) between two successive epimoric ratios is always an epimoric ratio.
* The difference (ie quotient) between two successive epimoric ratios is always an epimoric ratio.
* The sum of two successive epimoric ratios is either an epimoric ratio or an [[Superpartient|epimeric ratio]].
* The sum of two successive epimoric ratios is either an epimoric ratio or an [[Superpartient|epimeric ratio]].
* Every epimoric ratio can be split into two or more smaller epimoric ratios via the arithmetic mean.
* Every epimoric ratio can be split into the product of two epimoric ratios via the identity 1+1/n = (1+1/(2n))*(1+1/(2n+1)).
* 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) = cb/ad is epimoric.


Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a multiple of the fundamental (the same rule applies to all natural harmonics).
Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a multiple of the fundamental (the same rule applies to all natural harmonics).
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&lt;br /&gt;
&lt;br /&gt;
These ratios have some peculiar properties:&lt;br /&gt;
These ratios have some peculiar properties:&lt;br /&gt;
&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 (ie quotient) between two successive epimoric ratios is always an epimoric ratio.&lt;/li&gt;&lt;li&gt;The sum 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 two or more smaller epimoric ratios via the arithmetic mean.&lt;/li&gt;&lt;/ul&gt;&lt;br /&gt;
&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 (ie quotient) between two successive epimoric ratios is always an epimoric ratio.&lt;/li&gt;&lt;li&gt;The sum 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 via the identity 1+1/n = (1+1/(2n))*(1+1/(2n+1)).&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) = cb/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 multiple of the fundamental (the same rule applies to all natural harmonics).&lt;br /&gt;
Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a multiple of the fundamental (the same rule applies to all natural harmonics).&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;span style="background-color: initial;"&gt;&lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Superparticular_number" rel="nofollow"&gt;http://en.wikipedia.org/wiki/Superparticular_number&lt;/a&gt;&lt;/span&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>
&lt;span style="background-color: initial;"&gt;&lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Superparticular_number" rel="nofollow"&gt;http://en.wikipedia.org/wiki/Superparticular_number&lt;/a&gt;&lt;/span&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>

Revision as of 03:32, 9 August 2011

IMPORTED REVISION FROM WIKISPACES

This is an imported revision from Wikispaces. The revision metadata is included below for reference:

This revision was by author genewardsmith and made on 2011-08-09 03:32:11 UTC.
The original revision id was 244989655.
The revision comment was:

The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.

Original Wikitext content:

Superparticular numbers are ratios of the form (n+1)/n, or 1+1/n, where n is a whole number other than 1. 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:
* 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.
* The difference (ie quotient) between two successive epimoric ratios is always an epimoric ratio.
* The sum 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 via the identity 1+1/n = (1+1/(2n))*(1+1/(2n+1)).
* If a/b and c/d are Farey neighbors, that is if a/b < c/d and bc - ad = 1, then (c/d)/(a/b) = cb/ad is epimoric.

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


<span style="background-color: initial;">[[http://en.wikipedia.org/wiki/Superparticular_number]]</span>

Original HTML content:

<html><head><title>superparticular</title></head><body>Superparticular numbers are ratios of the form (n+1)/n, or 1+1/n, where n is a whole number other than 1. In ancient Greece they were known as Epimoric (επιμοριοσ, epimorios) ratios, which is literally translated as &quot;above a part.&quot;<br />
<br />
These ratios have some peculiar properties:<br />
<ul><li>The difference tone of the dyad is also the virtual fundamental.</li><li>The first 6 such ratios (<a class="wiki_link" href="/3_2">3/2</a>, <a class="wiki_link" href="/4_3">4/3</a>, <a class="wiki_link" href="/5_4">5/4</a>, <a class="wiki_link" href="/6_5">6/5</a>, <a class="wiki_link" href="/7_6">7/6</a>, <a class="wiki_link" href="/8_7">8/7</a>) are notable <a class="wiki_link" href="/harmonic%20entropy">harmonic entropy</a> minima.</li><li>The difference (ie quotient) between two successive epimoric ratios is always an epimoric ratio.</li><li>The sum of two successive epimoric ratios is either an epimoric ratio or an <a class="wiki_link" href="/Superpartient">epimeric ratio</a>.</li><li>Every epimoric ratio can be split into the product of two epimoric ratios via the identity 1+1/n = (1+1/(2n))*(1+1/(2n+1)).</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) = cb/ad is epimoric.</li></ul><br />
Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a multiple of the fundamental (the same rule applies to all natural harmonics).<br />
<br />
<br />
<span style="background-color: initial;"><a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Superparticular_number" rel="nofollow">http://en.wikipedia.org/wiki/Superparticular_number</a></span></body></html>