A124461 Row 1 of rectangular table A124460; also equals the antidiagonal sums of table A124460.
1, 2, 4, 9, 23, 66, 210, 731, 2744, 10959, 46058, 202028, 919386, 4321837, 20916763, 103958935, 529512396, 2759340117, 14690668955, 79813438230, 442057104246, 2493917931493, 14320972817368, 83652035642564, 496769855224824
Offset: 0
Keywords
Programs
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PARI
{a(n)=local(m=max(n,1),R=vector(m+1,r,vector(m+1,c,binomial(r+c-2,c-1)))); for(i=0,m,for(r=0,m,R[r+1]=Vec(sum(c=0,m,x^c*Ser(R[c+1])^r+O(x^(m+1))))));R[2][n+1]}
Formula
O.g.f.: A(x) = Sum_{n>=0} x^n*R_n(x) = Sum_{k>=0} x^k/(1 - x*R_k(x)), where R_n(x) is the o.g.f. of row n in table A124460.
Comments