A124835 Row sums of triangle A124834.

1, 2, 4, 9, 25, 91, 444, 2920, 25996, 314752, 5201874, 117719942, 3658433597, 156505343943, 9234365056453, 752841451059559, 84938741035295776, 13279814559055121447, 2880581923860441220144, 867855593621657824023139

Offset: 0

Author

Paul D. Hanna, Nov 09 2006

Keywords

• nonn

Examples

			A(x) = 1/(1-x) + x/((1-x)(1-x)) + x^2/((1-x)(1-2x)(1-x)) + x^3/((1-x)(1-3x)(1-3x)(1-x)) + x^4/((1-x)(1-4x)(1-6x)(1-4x)(1-x)) +...
		

Crossrefs

Cf. A124834, A124836.

Programs

PARI

{a(n)=sum(k=0,n,polcoeff(1/prod(j=0,k,1-binomial(k,j)*x +x*O(x^n)),n-k))}

Formula

G.f.: A(x) = Sum_{k>=0} x^n * Product_{k=0..n} 1/(1 - binomial(n,k)*x).