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A007879
Chimes made by clock striking the hour and half-hour.
6
1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1, 9, 1, 10, 1, 11, 1, 12, 1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1, 9, 1, 10, 1, 11, 1, 12, 1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1, 9, 1, 10, 1, 11, 1, 12
OFFSET
0,4
COMMENTS
Periodic sequence with period 24. - Michel Marcus, Jul 17 2013
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1).
FORMULA
From Hieronymus Fischer, Sep 25 2007: (Start)
G.f.: 1/(1-x^2)+x(12x^26-13x^24+1)/((1-x^24)(1-x^2)^2).
G.f.: (1+x-x^2-x^24-13x^25+x^26+12x^27)/((1-x^24)(1-x^2)^2).
a(n) = 1 + ((n-1)*(1-(-1)^n)/4) mod 12.
a(n) = 1 + ((n-1)*(n mod 2)/2) mod 12. (End)
MATHEMATICA
CoefficientList[Series[(1+x-x^2-x^24-13x^25+x^26+12x^27)/((1-x^24)(1-x^2)^2), {x, 0, 71}], x] (* Stefano Spezia, Mar 27 2022 *)
PROG
(PARI) a(n)= 1 + ((n-1)*(1-(-1)^n)/4) % 12 \\ Michel Marcus, Jul 17 2013
CROSSREFS
Sequence in context: A375038 A319338 A177815 * A057979 A152271 A133622
KEYWORD
nonn,easy
AUTHOR
Jan Wolitzky
STATUS
approved