Generator-offset property: Difference between revisions
m →Proof |
|||
Line 28: | Line 28: | ||
== Theorems == | == Theorems == | ||
=== Proposition 1 (Properties of SGA scales) === | === Proposition 1 (Properties of SGA scales) === | ||
Let ''S'' be a 3-step-size scale word in L, M, and s of length n, and suppose ''S'' is SGA. Then: | Let ''S'' be a 3-step-size scale word in L, M, and s of length ''n'', and suppose ''S'' is SGA. Then: | ||
# ''S'' is abstractly SV3 (i.e. SV3 for almost all tunings). | # ''S'' is abstractly SV3 (i.e. SV3 for almost all tunings). | ||
# ''S'' is of the form '' | # ''S'' is of the form ''a''x ''b''y ''b''z for some permutation (x, y, z) of (L, M, s). | ||
# The length of ''S'' is either odd, or 4 (and ''S'' is of the form | # The length of ''S'' is either odd, or 4 (and ''S'' is of the form xyxz). | ||
# S = | # ''S'' = ''a''X ''b''Y ''b''Z is obtained from some mode of the (single-period) mos ''a''X 2''b''W by replacing all the W's successively with alternating Y's and Z's (or alternating Z's and Y's for the other chirality, fixing the mode of ''a''X 2''b''W). | ||
# The two alternants differ by replacing one Y with a Z. | # The two alternants differ by replacing one Y with a Z. | ||
# ''S'' is pairwise-mos. That is, the following operations each result in a mos: setting L = M, setting L = s, and setting M = s. | # ''S'' is pairwise-mos. That is, the following operations each result in a mos: setting L = M, setting L = s, and setting M = s. |