login
A376731
Expansion of (1 - x^4 - x^5)/((1 - x^4 - x^5)^2 - 4*x^9).
4
1, 0, 0, 0, 1, 1, 0, 0, 1, 6, 1, 0, 1, 15, 15, 1, 1, 28, 70, 28, 2, 45, 210, 210, 46, 67, 495, 924, 496, 157, 1002, 3003, 3004, 1121, 1911, 8009, 12871, 8161, 4880, 18684, 43760, 43948, 23409, 41820, 126124, 184988, 133285, 113373, 324616, 647112, 657273, 454366
OFFSET
0,10
FORMULA
a(n) = 2*a(n-4) + 2*a(n-5) - a(n-8) + 2*a(n-9) - a(n-10).
a(n) = Sum_{k=0..floor(n/4)} binomial(2*k,2*n-8*k).
PROG
(PARI) my(N=60, x='x+O('x^N)); Vec((1-x^4-x^5)/((1-x^4-x^5)^2-4*x^9))
(PARI) a(n) = sum(k=0, n\4, binomial(2*k, 2*n-8*k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 03 2024
STATUS
approved