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A376725
Expansion of 1/((1 - x^4 - x^5)^2 - 4*x^9).
4
1, 0, 0, 0, 2, 2, 0, 0, 3, 10, 3, 0, 4, 28, 28, 4, 5, 60, 126, 60, 11, 110, 396, 396, 117, 188, 1001, 1716, 1009, 462, 2191, 5720, 5729, 2592, 4564, 15920, 24320, 16482, 12036, 39168, 84000, 84750, 51927, 93024, 249292, 353738, 269962, 258324, 666932, 1250142
OFFSET
0,5
FORMULA
a(n) = 2*a(n-4) + 2*a(n-5) - a(n-8) + 2*a(n-9) - a(n-10).
a(n) = (1/2) * Sum_{k=0..floor(n/4)} binomial(2*k+2,2*n-8*k+1).
PROG
(PARI) my(N=50, x='x+O('x^N)); Vec(1/((1-x^4-x^5)^2-4*x^9))
(PARI) a(n) = sum(k=0, n\4, binomial(2*k+2, 2*n-8*k+1))/2;
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 02 2024
STATUS
approved