A125280 Row sums of triangle A125280, which is the convolution triangle of A030266.

1, 2, 5, 15, 53, 217, 1011, 5260, 30041, 185677, 1228209, 8620874, 63792445, 495163451, 4015888557, 33923543492, 297706713081, 2708377382444, 25495655264883, 247952347547483, 2487743315817023, 25717746952124842

Offset: 0

Author

Paul D. Hanna, Nov 26 2006

Keywords

• nonn

Examples

			A(x) = 1 + 2*x + 5*x^2 + 15*x^3 + 53*x^4 + 217*x^5 + 1011*x^6 +...
where 1 - 1/(1 + x*A(x)) = G(x) is the g.f. of A030266:
G(x) = x + x^2 + 2*x^3 + 6*x^4 + 23*x^5 + 104*x^6 + 531*x^7 + 2982*x^8+..
		

Crossrefs

Cf. A125280, A030266.

Programs

PARI

{a(n)=local(G=x+x^2);for(i=0,n,G=x+x*subst(G,x,G+x^2*O(x^n))); polcoeff((-1+1/(1-G))/x,n,x)}

Formula

G.f.: A(x) = (1/x)*G(x)/(1 - G(x)) where G(x) = x + x*G(G(x)) is g.f. of A030266.