Distributional evenness

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Not to be confused with Maximal evenness.

A scale is distributionally even if equating all step sizes except one will always result in a MOS. MOSses are the only distributionally even binary scales. The term was originally defined as a generalization of maximal evenness specifically for binary scales; this is the most convenient generalization.

Technical definition

Let r ≥ 2 and let [math]\displaystyle{ S: \mathbb{Z}\to\mathbb{R} }[/math] be an r-ary periodic scale with length n (i.e. S(kn) = kP where P is the period), with step sizes x1, ..., xr, i.e. such that [math]\displaystyle{ \Delta S(i) := S(i+1)-S(i)\in \{x_1, ..., x_r\} \forall i \in \mathbb{Z}. }[/math] The scale S is distributionally even if for every i ∈ {1, ..., r}, (ΔS)−1(xi) mod n is a maximally even subset of [math]\displaystyle{ \mathbb{Z}/n. }[/math] (For the original definition of DE, simply set r = 2.)

Distributionally even scales over r letters are a subset of product words of r − 1 MOS scales, which can be thought of as temperament-agnostic Fokker blocks. All DE scales in this extended sense are also billiard scales.[1]

List of distributionally even circular words

Below is the complete list of distributionally even circular words up to 10 letters, up to equivalence under reassignment of letters.

1 Letter

1 letter, unary: 0

2 Letters

2 letters, unary: 00

2 letters, binary: 01

3 Letters

3 letters, unary: 000

3 letters, binary: 001

3 letters, ternary: 012

4 Letters

4 letters, unary: 0000

4 letters, binary: 0001, 0101

4 letters, ternary: 0102

4 letters, quaternary: 0123

5 Letters

5 letters, unary: 00000

5 letters, binary: 00001, 00101

5 letters, ternary: 00102, 01012

5 letters, quaternary: 01023

5 letters, quinary: 01234

6 Letters

6 letters, unary: 000000

6 letters, binary: 000001, 001001, 010101

6 letters, ternary: 001002, 012012

6 letters, quaternary: 010203, 012013

6 letters, quinary: 012034

6 letters, 6-ary: 012345

7 Letters

7 letters, unary: 0000000

7 letters, binary: 0000001, 0001001, 0010101

7 letters, ternary: 0001002, 0010201, 0101012, 0102012

7 letters, quaternary: 0010203, 0102013, 0102032, 0120123

7 letters, quinary: 0102034, 0120134, 0120314

7 letters, 6-ary: 0120345

7 letters, 7-ary: 0123456

8 Letters

8 letters, unary: 00000000

8 letters, binary: 00000001, 00010001, 00100101, 01010101

8 letters, ternary: 00010002, 01020102, 01021012

8 letters, quaternary: 00100203, 01012013, 01020103, 01021013, 01230123

8 letters, quinary: 01020304, 01023042, 01230124

8 letters, 6-ary: 01023045, 01230145, 01230425

8 letters, 7-ary: 01230456

8 letters, 8-ary: 01234567

9 Letters

9 letters, unary: 000000000

9 letters, binary: 000000001, 000010001, 001001001, 001010101

9 letters, ternary: 000010002, 001020102, 010101012, 012012012

9 letters, quaternary: 001002003, 001020103, 001020302, 010201023, 010201032, 012031023

9 letters, quinary: 001020304, 010201034, 010201304, 010203042, 012013014, 012031024, 012301234

9 letters, 6-ary: 010203045, 012031045, 012301245, 012301425, 012301435, 012304135

9 letters, 7-ary: 012034056, 012301456, 012304156, 012304256

9 letters, 8-ary: 012304567

9 letters, 9-ary: 012345678

10 Letters

10 letters, unary: 0000000000

10 letters, binary: 0000000001, 0000100001, 0001001001, 0010100101, 0101010101

10 letters, ternary: 0000100002, 0010200102, 0101201012, 0102102012

10 letters, quaternary: 0001002003, 0010200103, 0010200302, 0101201013, 0102301023, 0120120123, 0120310213

10 letters, quinary: 0010200304, 0102103014, 0102301024, 0102301043, 0102304023, 0120130214, 0120310214, 0120310413, 0123401234

10 letters, 6-ary: 0102030405, 0102301045, 0102304025, 0102304053, 0120130145, 0120130415, 0120310415, 0120340253, 0123401235

10 letters, 7-ary: 0102304056, 0120340256, 0120340563, 0123401256, 0123401536

10 letters, 8-ary: 0120340567, 0123401567, 0123405267

10 letters, 9-ary: 0123405678

10 letters, 10-ary: 0123456789

Related topics

References

  1. Sano, S., Miyoshi, N., & Kataoka, R. (2004). m-Balanced words: A generalization of balanced words. Theoretical computer science, 314(1-2), 97-120.