2.5.7 subgroup: Difference between revisions

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The 2.5.7 subgroup is a retraction of the [[7-limit]], obtained by removing prime 3. Its simplest expansion is the [[2.5.7.11 subgroup]], which adds prime 11.

A notable subset of the 2.5.7 subgroup is the 1.5.7 [[tonality diamond]], comprised of all intervals in which 1, 5 and 7 are the only allowable odd numbers, once all powers of 2 are removed, either for the intervals of the scale or the ratios between successive or simultaneously sounding notes of the composition. The complete list of intervals in the 1.5.7 tonality diamond within the octave is [[1/1]], [[8/7]], [[5/4]], [[7/5]], [[10/7]], [[8/5]], [[7/4]], and [[2/1]].

A notable subset of the 2.5.7 subgroup is the 1.5.7 [[tonality diamond]], comprised of all intervals in which 1, 5 and 7 are the only allowable odd numbers, once all powers of 2 are removed, either for the intervals of the scale or the ratios between successive or simultaneously sounding notes of the composition. The complete list of intervals in the 1.5.7 tonality diamond (which is the 7-odd-limit (1.3.5.7) with intervals of 3 removed) within the octave is [[1/1]], [[8/7]], [[5/4]], [[7/5]], [[10/7]], [[8/5]], [[7/4]], and [[2/1]].

Another such subset is the 1.5.7.25.35 tonality diamond, which adds the following intervals to the previous list: [[25/16]], [[25/14]], [[35/32]], [[64/35]], [[28/25]], and [[32/25]].

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 The 2.5.7 subgroup is a retraction of the [[7-limit]], obtained by removing prime 3. Its simplest expansion is the [[2.5.7.11 subgroup]], which adds prime 11.
-A notable subset of the 2.5.7 subgroup is the 1.5.7 [[tonality diamond]], comprised of all intervals in which 1, 5 and 7 are the only allowable odd numbers, once all powers of 2 are removed, either for the intervals of the scale or the ratios between successive or simultaneously sounding notes of the composition. The complete list of intervals in the 1.5.7 tonality diamond within the octave is [[1/1]], [[8/7]], [[5/4]], [[7/5]], [[10/7]], [[8/5]], [[7/4]], and [[2/1]].
+A notable subset of the 2.5.7 subgroup is the 1.5.7 [[tonality diamond]], comprised of all intervals in which 1, 5 and 7 are the only allowable odd numbers, once all powers of 2 are removed, either for the intervals of the scale or the ratios between successive or simultaneously sounding notes of the composition. The complete list of intervals in the 1.5.7 tonality diamond (which is the 7-odd-limit (1.3.5.7) with intervals of 3 removed) within the octave is [[1/1]], [[8/7]], [[5/4]], [[7/5]], [[10/7]], [[8/5]], [[7/4]], and [[2/1]].
 Another such subset is the 1.5.7.25.35 tonality diamond, which adds the following intervals to the previous list: [[25/16]], [[25/14]], [[35/32]], [[64/35]], [[28/25]], and [[32/25]].