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A101285 Rounded frequencies in Hertz of the notes of the C major music scale beginning at A (A Minor equal-tempered).

%I A101285 #23 Feb 06 2015 17:03:57
%S A101285 55,62,65,73,82,87,98,110,123,131,147,165,175,196,220,247,262,294,330,
%T A101285 349,392,440,494,523,587,659,698,784,880,988,1047,1175,1319,1397,1568,
%U A101285 1760,1976,2093,2349,2637,2794,3136,3520,3951,4186,4699,5274,5588,6272
%N A101285 Rounded frequencies in Hertz of the notes of the C major music scale beginning at A (A Minor equal-tempered).
%C A101285 The scale is equal-tempered ("Wohltemperiert"), introduced by Johann Sebastian Bach.
%C A101285 Subsequence of A101286, obtained by removal of the 5 black keys' frequencies in each block of 12 keys. - _R. J. Mathar_, Mar 12 2008
%H A101285 T. Yahaya Abdullah, <a href="http://www.angelfire.com/in2/yala/4scales.htm">Music Scales</a>, part of Synthesizers, Music and Television.
%H A101285 Wikipedia, <a href="http://en.wikipedia.org/wiki/Equal_temperament">Equal temperament</a>
%H A101285 Wikipedia, <a href="http://en.wikipedia.org/wiki/Aeolian_scale">Aeolian scale</a>
%F A101285 From _David Wasserman_, Mar 17 2008: (Start)
%F A101285 a(7n) = round(55*2^(n-1/6));
%F A101285 a(7n+1) = 55*2^n;
%F A101285 a(7n+2) = round(55*2^(n+1/6));
%F A101285 a(7n+3) = round(55*2^(n+1/4));
%F A101285 a(7n+4) = round(55*2^(n+5/12));
%F A101285 a(7n+5) = round(110*2^(n-5/12));
%F A101285 a(7n+6) = round(110*2^(n-1/3)). (End)
%F A101285 a(n) = round(55*2^(int(3*(4*k-1)/7-1)/12)). - _Federico Provvedi_, Feb 14 2014
%p A101285 A101286x := proc(n) 55*2.0^((n-1)/12.0) ; end: A101285x := proc(n) if n >= 8 then 2*A101285x(n-7) ; else A101286x(op(n,[1,3,4,6,8,9,11])) ; fi ; end: A101285 := proc(n) round(A101285x(n)) ; end: seq(A101285(n),n=1..80) ; # _R. J. Mathar_, Mar 12 2008
%t A101285 Table[Round[55*2^((Floor[3(4k-1)/7]-1)/12)],{k,1,49}] (* _Federico Provvedi_, Feb 14 2014 *)
%o A101285 (PARI) forstep(i = 0, 100, [2, 1, 2, 2, 1, 2, 2], print(round(55*2^(i/12)))) \\ _David Wasserman_, Mar 17 2008
%Y A101285 Cf. A071831, A071832, A071833.
%K A101285 nonn
%O A101285 1,1
%A A101285 Angela Johansson (angvi798(AT)student.liu.se), Dec 20 2004
%E A101285 More terms from Jonathan R. Love (japanada11(AT)yahoo.ca) and _R. J. Mathar_, Mar 08 2007