Rank-3 scale: Difference between revisions

Lhearne (talk | contribs)
m Product words: putting Flora's edit back cos Flora is doing the work on fokker blocks / product words
Lhearne (talk | contribs)
m italicized scale forms
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Not all trivalent scales are PWF. Only a single scale - ''abcba'' - is trivalent and not PWF.
Not all trivalent scales are PWF. Only a single scale - ''abcba'' - is trivalent and not PWF.


Only a single PWF scale is mirror-symmetric - abacaba.
Only a single PWF scale is mirror-symmetric - ''abacaba''.


Apart from ''abacaba'', PWF scales can be generated by an alternating generator sequence of two generators, modulo the period.
Apart from ''abacaba'', PWF scales can be generated by an alternating generator sequence of two generators, modulo the period.
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PWF and pairwise-DE scales include the same number of instances of steps of 2 of the 3 different step sizes, apart from ''abacaba''.
PWF and pairwise-DE scales include the same number of instances of steps of 2 of the 3 different step sizes, apart from ''abacaba''.


The scale abacaba is the only mirror-symmetric PWF / PDE / PMOS, and the only mirror-symmetric trivalent scale.
The scale ''abacaba'' is the only mirror-symmetric PWF / PDE / PMOS, and the only mirror-symmetric trivalent scale.


The scales ''a…ba…c'', and the scale abacaba are the only mirror-symmetric pairwise-DE scales, and the only mirror-symmetric MV3 scales.
The scales ''a…ba…c'', and the scale abacaba are the only mirror-symmetric pairwise-DE scales, and the only mirror-symmetric MV3 scales.
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'''Conjecture''': The only SN scale that is trivalent is ''abacaba''.
'''Conjecture''': The only SN scale that is trivalent is ''abacaba''.


'''Conjecture''': The only SN scales that are MV3 are abacaba, and scales of the form ''a…ba…c''.
'''Conjecture''': The only SN scales that are MV3 are ''abacaba'', and scales of the form ''a…ba…c''.


'''Conjecture''': The only SN scales that are MV3, and have mean variety < 3 are those of the form ''a…ba…c''.
'''Conjecture''': The only SN scales that are MV3, and have mean variety < 3 are those of the form ''a…ba…c''.