cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A371579 G.f. satisfies A(x) = ( 1 + x*A(x)^(5/2) * (1 + x*A(x))^2 )^2.

Original entry on oeis.org

1, 2, 15, 134, 1367, 15032, 173836, 2083806, 25660383, 322666882, 4125822703, 53482104104, 701223274308, 9283066366256, 123912439591104, 1665895096499278, 22537232138264271, 306586712969384678, 4191205834907493725, 57548344232637695030, 793311718924341065567
Offset: 0

Views

Author

Seiichi Manyama, Mar 28 2024

Keywords

Crossrefs

Cf. A371574.

Programs

  • 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(s*k, 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(s*k,n-k)/(t*k+u*(n-k)+r).