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A360089
a(n) = Sum_{k=0..n} (-1)^k * binomial(5*k,n-k).
2
1, -1, -4, -1, 21, 29, -80, -244, 153, 1473, 836, -6920, -12220, 23209, 91213, -21511, -510680, -457965, 2210520, 4921941, -6271749, -33288595, -3876765, 173223185, 214943855, -682969376, -1912499375, 1498348275, 11882164650, 5332839025, -57402248250, -92821609874
OFFSET
0,3
FORMULA
a(n) = -a(n-1) - 5*a(n-2) - 10*a(n-3) - 10*a(n-4) - 5*a(n-5) - a(n-6).
G.f.: 1/(1 + x*(1+x)^5).
PROG
(PARI) a(n) = sum(k=0, n, (-1)^k*binomial(5*k, n-k));
(PARI) my(N=40, x='x+O('x^N)); Vec(1/(1+x*(1+x)^5))
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Jan 25 2023
STATUS
approved