OFFSET
0,11
COMMENTS
a(n) is the number of partitions of n into parts 5, 9, and 10. - Michel Marcus, Dec 12 2022
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..5000
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,1,0,0,0,1,1,0,0,0,-1,-1,0,0,0,-1,0,0,0,0,1).
FORMULA
a(n) = floor((n^2-12*n+140)/900 + (n+5)*((n+4) mod 5)/50 + ((8*n^2+3*n+4) mod 9)/9). - Hoang Xuan Thanh, Sep 21 2025
MATHEMATICA
CoefficientList[Series[1/((1-x^5)(1-x^9)(1-x^10)), {x, 0, 80}], x] (* Harvey P. Dale, Mar 05 2019 *)
PROG
(Magma) R<x>:=PowerSeriesRing(Integers(), 90); Coefficients(R!( 1/((1-x^5)*(1-x^9)*(1-x^10)) )); // G. C. Greubel, Dec 11 2022
(SageMath)
def A025891_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P( 1/((1-x^5)*(1-x^9)*(1-x^10)) ).list()
A025891_list(90) # G. C. Greubel, Dec 11 2022
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved
