Generator-offset property: Difference between revisions

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==== Proof ====
==== Proof ====
Assume that the generator is a ''k''-step and ''k'' is even. (If ''k'' is not even, invert the generator.) On some tonic ''p'' we have a chain of ceil(''n''/2) notes and on some other note ''p′'' = ''p'' + offset (not on the first chain) we'll have floor(''n''/2) notes.
Assume that the generator is a ''k''-step and ''k'' is even. (If ''k'' is not even, invert the generator.) On some note ''p'' we have a chain of ceil(''n''/2) notes and on ''p′'' = ''p'' + offset we'll have floor(''n''/2) notes.


We must have gcd(''k'', ''n'') = 1. If not, since ''n'' is odd, gcd(''k'', ''n'') is an odd number at least 3, and by well-formedness with respect to the generator, the generators must form more than 2 parallel chains.
We must have gcd(''k'', ''n'') = 1. If not, since ''n'' is odd, gcd(''k'', ''n'') is an odd number at least 3, and by well-formedness with respect to the generator, the generators must form more than 2 parallel chains.