Ternary scale theorems: Difference between revisions
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==== Statement (4) ==== | ==== Statement (4) ==== | ||
Assume ''S'' is ''a''X ''b''Y ''b''Z, ''a'' odd. If ''b'' = 1, there's nothing to prove, so assume ''b'' > 1. | |||
Assume, possibly after inverting the generator, that the imperfect generator of ''T'' has ''j'' + 1 W's and the perfect generator has ''j'' W's. Consider the two alternants, detemperings of the generator ''i''X + ''j''W of the ''a''X 2''b''W mos ''T''(X, W) = ''S''(X, W, W) where gcd(''j'', 2''k'') = 1. | Assume, possibly after inverting the generator, that the imperfect generator of ''T'' has ''j'' + 1 W's and the perfect generator has ''j'' W's. Consider the two alternants, detemperings of the generator ''i''X + ''j''W of the ''a''X 2''b''W mos ''T''(X, W) = ''S''(X, W, W) where gcd(''j'', 2''k'') = 1. | ||
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==== Statement (5) ==== | ==== Statement (5) ==== | ||
Odd-numbered SGA scales are [[Fokker block]]s (in the 2-dimensional lattice generated by the generator and the offset). To see this, consider the following lattice depiction of such a scale: | |||
x x x ... x | x x x ... x | ||
x x x ... x x | x x x ... x x | ||
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==== Statement (6) ==== | ==== Statement (6) ==== | ||
Consider the mos ''a''X 2''b''W as chunks of X separated by W (tempering Y and Z together into W). Eliminating every other W (corresponding to either Y or Z) turns it into a mos: | |||
# The chunk sizes of X form a mos, and taking every ''k''th note of an ''n''-note mos yields a mos. | # The chunk sizes of X form a mos, and taking every ''k''th note of an ''n''-note mos yields a mos. | ||
# The sum of sizes of consecutive chunks of X (1st chunk with 2nd chunk, 3rd with 4th, ...) must form a mos. | # The sum of sizes of consecutive chunks of X (1st chunk with 2nd chunk, 3rd with 4th, ...) must form a mos. | ||