A124529 - OEIS

%I #3 Mar 30 2012 18:37:01

%S 1,2,6,29,190,1562,15457,179034,2377092,35599701,593731310,

%T 10914169312,219252994039,4779086510108,112341582757512,

%U 2833025331800643,76293601822430388,2185288262904326236,66338823231846583471

%N a(n) = Sum_{k=0..n} k!*A124526(n+k,k) for n>=0.

%C Equals diagonal sums of triangle A124418: a(n) = Sum_{k=0..n} A124418(n+k,k) for n>=0 (conjecture).

%o (PARI) {a(n)=sum(k=0,n,k!*((n+k)\2)!*((n+k+1)\2)!*polcoeff(polcoeff(exp((1+y)*(exp(x+x*O(x^n))-1)),(n+k)\2),k) *polcoeff(polcoeff(exp((1+y)*(exp(x+x*O(x^n))-1)),(n+k+1)\2),k))}

%Y Cf. A124526, A124527, A124528; A124418.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Nov 08 2006