This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A124529 #3 Mar 30 2012 18:37:01 %S A124529 1,2,6,29,190,1562,15457,179034,2377092,35599701,593731310, %T A124529 10914169312,219252994039,4779086510108,112341582757512, %U A124529 2833025331800643,76293601822430388,2185288262904326236,66338823231846583471 %N A124529 a(n) = Sum_{k=0..n} k!*A124526(n+k,k) for n>=0. %C A124529 Equals diagonal sums of triangle A124418: a(n) = Sum_{k=0..n} A124418(n+k,k) for n>=0 (conjecture). %o A124529 (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 A124529 Cf. A124526, A124527, A124528; A124418. %K A124529 nonn %O A124529 0,2 %A A124529 _Paul D. Hanna_, Nov 08 2006