A124531 Row 1 of rectangular table A124530.

1, 1, 2, 5, 16, 62, 274, 1332, 6978, 38873, 228090, 1399625, 8933506, 59066261, 403241292, 2835267821, 20490128048, 151951503074, 1154770194362, 8983396031267, 71473650532630, 581142591346325, 4825842125683150

Offset: 0

Author

Paul D. Hanna, Nov 05 2006

Keywords

• nonn

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.

Crossrefs

Cf. A124530 (table); other rows: A124532, A124533, A124534, A124535, A124536.

Programs

PARI

a(n)=local(R);R=vector(n+2,r,vector(n+2,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[2][n+1]

Formula

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