Structure implies multiplicity

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In

diatonic transpositions of that series. Structure refers to the intervals in relation to the circle of fifths; multiplicity refers to the number of times each different (adjacent) interval pattern occurs. The property was first described by John Clough and Gerald Myerson in "Variety and Multiplicity in Diatonic Systems" (1985). (Johnson 2003
, pp. 68, 151)

Structure implies multiplicity is true of the

, and any subset.

For example,

scale degrees
gives three interval patterns: M2-M2, M2-m2, m2-M2.

three member diatonic subset of the C major scale, C-D-E transposed to all scale degrees

C-D-E on the circle of fifths

On the circle of fifths:

C G D A E B F (C)
  1 2 1 2 1 2  3

E and C are three notes apart, C and D are two notes apart, D and E two notes apart. Just as the distance around the circle of fifths between forms the interval pattern 3-2-2, M2-M2 occurs three times, M2-m2 occurs twice, and m2-M2 occurs twice.

Myhill's property or maximal evenness
.

References

Further reading

  • Clough, John and Myerson, Gerald (1985). "Variety and Multiplicity in Diatonic Systems", Journal of Music Theory 29: 249-70.
  • Agmon, Eytan (1989). "A Mathematical Model of the Diatonic System", Journal of Music Theory 33: 1-25.
  • Agmon, Eytan (1996). "Coherent Tone-Systems: A Study in the Theory of Diatonicism", Journal of Music Theory 40: 39-59.