Rank-3 scale: Difference between revisions

Lhearne (talk | contribs)
Rank-2 scales: Fixed typo
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Lhearne (talk | contribs)
MV3 and SV3 scales: Edited expression
Tags: Mobile edit Mobile web edit
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== MV3 scales ==
== MV3 and SV3 scales ==
[[Maximum variety]] 3 (MV3) scales are a generalization of MOS scales (the scales of MV2) into rank-3. We often speak of strict-variety 3 (SV3) instead, meaning that every interval class has ''exactly'' three sizes. SV3 scales are also called '''trivalent'''.
[[Maximum variety]] 3 (MV3) scales are a generalization of MOS scales (the scales of MV2) into rank-3. An important subset strict-variety 3 (SV3) scales, which are a generalisation of strict MOS scales into rank-3, where-in every interval class has ''exactly'' three sizes. In academic literature these scales are instead described as '''trivalent'''.


'''Conjecture:''' For all odd-cardinality SV3 scales apart from the scales '''''abacaba''''', and its repetitions '''''abacabaabacaba''''' etc., at least two of the three steps must occur the same number of times.
'''Conjecture:''' For all odd-cardinality SV3 scales apart from the scales '''''abacaba''''', and its repetitions '''''abacabaabacaba''''' etc., at least two of the three steps must occur the same number of times.
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All GO scales of odd cardinality are MV3. The only GO scale of even cardinality is '''''abac'''''.
All GO scales of odd cardinality are MV3. The only GO scale of even cardinality is '''''abac'''''.


'''Conjecture:''' The only mirror-symmetric MV3 scales are abacaba (and its repetitions) and the scales of the form '''''a…ba…c''''' (and their repetitions). Therefore the only MV3 scales that are mirror-symmetric are the only MV3 scales that are also 3-[[SN scales]] (introduced below).
'''Conjecture:''' The only mirror-symmetric MV3 scales are '''''abacaba''''' (and its repetitions) and the scales of the form '''''a…ba…c''''' (and their repetitions). Therefore the only MV3 scales that are mirror-symmetric are the only MV3 scales that are also 3-[[SN scales]] (introduced below).


== Product words ==
== Product words ==