A381832 G.f. A(x) satisfies A(x) = C(x*A(x)^3) / (1 - x), where C(x) is the g.f. of A000108.
1, 2, 10, 81, 796, 8616, 98973, 1184324, 14602486, 184219731, 2366543116, 30851212416, 407106050261, 5427274340091, 72986372975716, 988937692146346, 13487903251385562, 185022817888443780, 2551096865411701371, 35335463473311506321, 491444773227779518956, 6860346682881319595632
Offset: 0
Keywords
Programs
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PARI
a(n) = sum(k=0, n, binomial(5*k+1, k)*binomial(n+2*k, n-k)/(5*k+1));
Formula
a(n) = Sum_{k=0..n} binomial(5*k+1,k) * binomial(n+2*k,n-k)/(5*k+1).