A371584 G.f. satisfies A(x) = ( 1 + x*A(x)^(5/2) / (1 - x*A(x))^2 )^2.
1, 2, 15, 138, 1435, 16074, 189238, 2308640, 28927579, 370084760, 4814147248, 63482437724, 846678807008, 11401357736202, 154800183842738, 2116833422071448, 29128279396373599, 403029526567463278, 5603854904038673961, 78260199678455985082, 1097257906416031628336
Offset: 0
Keywords
Crossrefs
Cf. A371579.
Programs
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PARI
a(n, r=2, s=2, t=5, u=2) = r*sum(k=0, n, binomial(t*k+u*(n-k)+r, k)*binomial(n+(s-1)*k-1, n-k)/(t*k+u*(n-k)+r));
Formula
If g.f. satisfies A(x) = ( 1 + x*A(x)^(t/r) / (1 - x*A(x)^(u/r))^s )^r, then a(n) = r * Sum_{k=0..n} binomial(t*k+u*(n-k)+r,k) * binomial(n+(s-1)*k-1,n-k)/(t*k+u*(n-k)+r).