A360088 a(n) = Sum_{k=0..n} (-1)^k * binomial(4*k,n-k).
1, -1, -3, 1, 13, 4, -49, -46, 165, 284, -476, -1417, 1003, 6220, -110, -24644, -14831, 88184, 113224, -278288, -619744, 715647, 2891977, -1036173, -12068353, -3381661, 45588556, 41600921, -154355594, -259984429, 448828716, 1305250324, -964837159, -5754843123
Offset: 0
Links
- Index entries for linear recurrences with constant coefficients, signature (-1,-4,-6,-4,-1).
Programs
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PARI
a(n) = sum(k=0, n, (-1)^k*binomial(4*k, n-k));
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PARI
my(N=40, x='x+O('x^N)); Vec(1/(1+x*(1+x)^4))
Formula
a(n) = -a(n-1) - 4*a(n-2) - 6*a(n-3) - 4*a(n-4) - a(n-5).
G.f.: 1/(1 + x*(1+x)^4).