A124534 Row 4 of rectangular table A124530.

1, 1, 5, 25, 113, 608, 3535, 21844, 141809, 959882, 6738850, 48877221, 365145267, 2803002587, 22066904802, 177881536038, 1466278969213, 12345543329079, 106069531868783, 929158597546721, 8292429187449462, 75348425058995464

Offset

0,3

Comments

In table A124530, the g.f. of row n, R_n(y), simultaneously satisfies: R_n(y) = Sum_{k>=0} y^k*R_k(y)^(n*k) for n>=0.

Links

Table of n, a(n) for n=0..21.

Formula

G.f.: A(x) = Sum_{n>=0} x^n*R_n(x)^(4n), where R_n(x) is the g.f. of row n in table A124530.

Prog

(PARI) a(n)=local(R); R=vector(n+5, r, vector(n+5, c, if(r==1 || c<=2, 1, r^(c-2)))); for(i=0, n, for(r=0, n, R[r+1]=Vec(sum(c=0, n, x^c*Ser(R[c+1])^(r*c)+O(x^(n+1)))))); R[5][n+1]

Crossrefs

Cf. A124530 (table); other rows: A124531, A124532, A124533, A124535, A124536.

Sequence in context: A183926 A092440 A196985 * A369769 A261383 A089947

Adjacent sequences: A124531 A124532 A124533 * A124535 A124536 A124537

Keyword

nonn

Author

Paul D. Hanna, Nov 05 2006

Status

approved