The number common to all identities in the ratios of one tonality -- the common anchor; the characteristic of a series of ratios that determines them as a tonality.
[For example,] in the 8/5 Otonality the Numerary Nexus is 5, as seen in the sequence of the six Odentities:
11/10 [= 11/5 in Partch's theory]
9/5
7/5
6/5
1/1 (= 5/5)
8/5
In the 5/4 Utonality the Numerary Nexus is also 5, as seen in the sequence of the six Udentities:
20/11 [= 5/11]
10/9 [= 5/9]
10/7 [= 5/7]
5/3
1/1 (= 5/5)
5/4
How about a clearer example, like
5 6 7 8 9 10 - - - - - -- 5 5 5 5 5 5
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