OFFSET

1,1

COMMENTS

Number of equal microtone intervals dividing a musical octave, so that it is (formally) possible to compose one octave (according to the diatonic scale) of two semi-tone-steps and five whole-tone-steps, each being a multiple of the microtone interval.

LINKS

Analysis of equal temperament tuning systems (German language)

EXAMPLE

12 = 2*1 + 5*2

17 = 2*1 + 5*3

19 = 2*2 + 5*3

22 = 2*1 + 5*4

...

MATHEMATICA

Union[2*First[#]+5*Last[#]&/@Subsets[Range[20], {2}]] (* Harvey P. Dale, Mar 28 2012 *)

PROG

(Haskell)

filter (\n -> [ (s, w) | s<-[1..n], w<-[(s+1)..n], 2*s+5*w == n ] /= []) [1..]

CROSSREFS

KEYWORD

nonn

AUTHOR

Jan Behrens (jbe-oeis(AT)magnetkern.de), Jul 17 2009

STATUS

approved