A364760 G.f. satisfies A(x) = 1 / (1 + x*(1 + x*A(x))^2).
1, -1, -1, 4, 1, -21, 14, 111, -195, -529, 1837, 1792, -14772, 2300, 105431, -126697, -657427, 1650427, 3285795, -16211352, -8308737, 135770125, -79748628, -990431659, 1700106664, 6098396204, -20258923714, -27342511804, 193913175511, 12018867589
Offset: 0
Keywords
Programs
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PARI
a(n) = sum(k=0, n, (-1)^k*binomial(n+1, k)*binomial(2*k, n-k))/(n+1);
Formula
a(n) = (1/(n+1)) * Sum_{k=0..n} (-1)^k * binomial(n+1,k) * binomial(2*k,n-k).