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Z-relations in 31-et by subset

🔗Paul G Hjelmstad <paul_hjelmstad@allianzlife.com>

10/6/2005 12:13:23 PM

Just a quick explanation of the file I just posted -

The data for 31-et has over 17.3 million rows.

The clustering of Z-relations for 31,6 through 31,15 follows a pattern
of being in multiples of 5, except for three cases. (Twins in 31,10
and 31,11 and quadruplets in 31,15). I am still a long ways off from
developing a formula for Z-relations (probably will have many cases,
if such a solution exists).

Here's a quick summary:

14-et multiples of 12
15-et multiples of 10
17-et multiples of 8
19-et multiples of 6
22-et multiples of 5
31-et almost completely multiples of 5

I want to show that Z-related sets can be mapped to each other through
simple transformations. Here's some more interesting information
on where Z-relations first appear, from Jon Wild:

First Z-pair: 8-tet (1 tetrachordal pair, (0134) and (0125))
First Z-triplets: 16-tet (3 hexachordal and 4 heptachordal
triplets)
First Z-quadruplets: 16-tet (3 8-note quadruplets)
First Z-quintuplets: 24-tet (3 10-note and 2 11-note quintuplets)
First Z-sextuplets: 20-tet (2 10-note sextuplets)
First Z-heptuplets: 28-tet (1 9-, 3 11- and 9 13-note heptuplets)
First Z-octuplets: 24-tet (1 9-, 3 10-, 2 11- and 75 12-note
octuplets)
First Z-nonuplets: 28-tet (6 12-note nonuplets)
First Z-decuplets: 28-tet (6 12-note and 12 14-note decuplets)
First Z-11-plets:
First Z-dodecuplets: 24-tet (3 12-note dodecuplets)

Here's Z relations by tet and flavor:

8-tet: Z-2
9-tet:
10-tet: Z-2
11-tet:
12-tet: Z-2
13-tet: Z-2
14-tet: Z-2
15-tet: Z-2
16-tet: Z-2, 3, 4
17-tet: Z-2
18-tet: Z-2, 3, 4
19-tet: Z-2
20-tet: Z-2, 3, 4, 6
21-tet: Z-2, 3, 4
22-tet: Z-2, 3, 4, 6
23-tet: Z-2, 3
24-tet: Z-2, 3, 4, 5, 6, 8, 12
25-tet: Z-2, 3, 4
26-tet: Z-2, 3, 4, 6, 8
27-tet: Z-2, 3, 4, 6
28-tet: Z-2, 3, 4, 5, 6, 7, 8, 9, 10, 12

this last bit says that 26-tet, for example, possesses pairs,
triplets, quartets, sextets and octets of Z-related chords.

Paul