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A017882
Expansion of 1/(1-x^9-x^10-x^11-x^12-x^13-x^14-x^15).
10
1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 6, 5, 5, 6, 8, 11, 15, 21, 28, 33, 36, 38, 40, 43, 48, 56, 71, 94, 122, 152, 182, 211, 239, 266, 294, 332, 390, 474, 586, 725, 888, 1071, 1266, 1466
OFFSET
0,20
COMMENTS
Number of compositions (ordered partitions) of n into parts 9, 10, 11, 12, 13, 14 and 15. - Ilya Gutkovskiy, May 27 2017
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,1,1,1,1,1,1,1).
FORMULA
a(n) = a(n-9) +a(n-10) +a(n-11) +a(n-12) +a(n-13) +a(n-14) +a(n-15) for n>14. - Vincenzo Librandi, Jul 01 2013
MATHEMATICA
CoefficientList[Series[1 / (1 - Total[x^Range[9, 15]]), {x, 0, 80}], x] (* Vincenzo Librandi, Jul 01 2013 *)
PROG
(Magma)
m:=70; R<x>:=PowerSeriesRing(Integers(), m);
Coefficients(R!(1/(1-x^9-x^10-x^11-x^12-x^13-x^14-x^15))); // Vincenzo Librandi, Jul 01 2013
(SageMath)
def A017882_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P( (1-x)/(1-x-x^9+x^(16)) ).list()
A017882_list(80) # G. C. Greubel, Sep 25 2024
KEYWORD
nonn,easy
STATUS
approved