OFFSET
0,5
COMMENTS
Number of partitions of n into parts 1, 4, 5 and 11. - Ilya Gutkovskiy, May 17 2017
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (1,0,0,1,0,-1,0,0,-1,1,1,-1,0,0, -1,0,1,0,0,1,-1).
FORMULA
a(n) = floor((2*n^3 + 63*n^2 + 580*n + 88*(-1)^n + 2760)/2640 + (1/5)*((-1)^[(n mod 5)>1] + [(n mod 5)=2])). - Hoang Xuan Thanh, Aug 06 2025
MATHEMATICA
CoefficientList[Series[1/((1 - x)*(1 - x^4)*(1 - x^5)*(1 - x^11)), {x, 0, 50}], x] (* G. C. Greubel, May 17 2017 *)
PROG
(PARI) my(x='x+O('x^50)); Vec(1/((1 - x)*(1 - x^4)*(1 - x^5)*(1 - x^11))) \\ G. C. Greubel, May 17 2017
(PARI) a(n) = floor((2*n^3 + 63*n^2 + 580*n + 88*(-1)^n + 2760)/2640 + (1/5)*[1, 1, 0, -1, -1][n%5+1]) \\ Hoang Xuan Thanh, Aug 06 2025
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved
