Harmonic limit

From Xenharmonic Wiki
Revision as of 03:09, 5 January 2015 by Wikispaces>hstraub (**Imported revision 536218044 - Original comment: **)
Jump to navigation Jump to search

IMPORTED REVISION FROM WIKISPACES

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

This revision was by author hstraub and made on 2015-01-05 03:09:46 UTC.
The original revision id was 536218044.
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:

A positive rational number q belongs to the **p-limit**, called the **p harmonic** or **prime limit**, for a given [[prime number]] p if and only if it can be factored into primes (with positive or negative integer exponents) of size less than or equal to p. For any prime number p, the set of all rational numbers in the p-limit defines a [[http://en.wikipedia.org/wiki/Free_abelian_group|finitely generated free abelian group]]. The rank of this group is equal to pi(p), the number of prime numbers less than or equal to p. Hence, for example, the rank of the [[7-limit]] is 4, as it is generated by 2, 3, 5 and 7. Another way to express the p-limit is that it consists of the ratios of [[http://en.wikipedia.org/wiki/Smooth_number|p-smooth numbers]], where a p-smooth number is an integer with prime factors no larger than p.

==List of small p-limits== 
With increasing limits, the tonal space becomes more dense.
* [[2-limit]] contains only multiples of the [[octave]] (2/1), see [[1edo]]
* [[3-limit]] contains [[3_2|3/2]], the [[just perfect fifth]]
* [[5-limit]] contains [[5_4|5/4]], the just major third
* [[7-limit]] contains [[7_4|7/4]], the harmonic seventh
* [[11-limit]] contains [[11_8|11/8]], the Alphorn-Fa
* [[13-limit]]
* [[17-limit]]
* [[19-limit]]
* [[23-limit]]
* [[47-limit]]

==See also== 
* [[Odd limit]]
* [[Harmonic Class (HC)]]
* [[consistency]]
* [[http://en.wikipedia.org/wiki/Limit_%28music%29|Limit (music) - Wikipedia]] (covers also the distinction between odd-limit and prime-limit)
* [[http://en.wikipedia.org/wiki/St%C3%B8rmer%27s_theorem|Størmer's theorem - Wikipedia]]

Original HTML content:

<html><head><title>Harmonic Limit</title></head><body>A positive rational number q belongs to the <strong>p-limit</strong>, called the <strong>p harmonic</strong> or <strong>prime limit</strong>, for a given <a class="wiki_link" href="/prime%20number">prime number</a> p if and only if it can be factored into primes (with positive or negative integer exponents) of size less than or equal to p. For any prime number p, the set of all rational numbers in the p-limit defines a <a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Free_abelian_group" rel="nofollow">finitely generated free abelian group</a>. The rank of this group is equal to pi(p), the number of prime numbers less than or equal to p. Hence, for example, the rank of the <a class="wiki_link" href="/7-limit">7-limit</a> is 4, as it is generated by 2, 3, 5 and 7. Another way to express the p-limit is that it consists of the ratios of <a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Smooth_number" rel="nofollow">p-smooth numbers</a>, where a p-smooth number is an integer with prime factors no larger than p.<br />
<br />
<!-- ws:start:WikiTextHeadingRule:0:&lt;h2&gt; --><h2 id="toc0"><a name="x-List of small p-limits"></a><!-- ws:end:WikiTextHeadingRule:0 -->List of small p-limits</h2>
 With increasing limits, the tonal space becomes more dense.<br />
<ul><li><a class="wiki_link" href="/2-limit">2-limit</a> contains only multiples of the <a class="wiki_link" href="/octave">octave</a> (2/1), see <a class="wiki_link" href="/1edo">1edo</a></li><li><a class="wiki_link" href="/3-limit">3-limit</a> contains <a class="wiki_link" href="/3_2">3/2</a>, the <a class="wiki_link" href="/just%20perfect%20fifth">just perfect fifth</a></li><li><a class="wiki_link" href="/5-limit">5-limit</a> contains <a class="wiki_link" href="/5_4">5/4</a>, the just major third</li><li><a class="wiki_link" href="/7-limit">7-limit</a> contains <a class="wiki_link" href="/7_4">7/4</a>, the harmonic seventh</li><li><a class="wiki_link" href="/11-limit">11-limit</a> contains <a class="wiki_link" href="/11_8">11/8</a>, the Alphorn-Fa</li><li><a class="wiki_link" href="/13-limit">13-limit</a></li><li><a class="wiki_link" href="/17-limit">17-limit</a></li><li><a class="wiki_link" href="/19-limit">19-limit</a></li><li><a class="wiki_link" href="/23-limit">23-limit</a></li><li><a class="wiki_link" href="/47-limit">47-limit</a></li></ul><br />
<!-- ws:start:WikiTextHeadingRule:2:&lt;h2&gt; --><h2 id="toc1"><a name="x-See also"></a><!-- ws:end:WikiTextHeadingRule:2 -->See also</h2>
 <ul><li><a class="wiki_link" href="/Odd%20limit">Odd limit</a></li><li><a class="wiki_link" href="/Harmonic%20Class%20%28HC%29">Harmonic Class (HC)</a></li><li><a class="wiki_link" href="/consistency">consistency</a></li><li><a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Limit_%28music%29" rel="nofollow">Limit (music) - Wikipedia</a> (covers also the distinction between odd-limit and prime-limit)</li><li><a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/St%C3%B8rmer%27s_theorem" rel="nofollow">Størmer's theorem - Wikipedia</a></li></ul></body></html>