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A124529
a(n) = Sum_{k=0..n} k!*A124526(n+k,k) for n>=0.
3
1, 2, 6, 29, 190, 1562, 15457, 179034, 2377092, 35599701, 593731310, 10914169312, 219252994039, 4779086510108, 112341582757512, 2833025331800643, 76293601822430388, 2185288262904326236, 66338823231846583471
OFFSET
0,2
COMMENTS
Equals diagonal sums of triangle A124418: a(n) = Sum_{k=0..n} A124418(n+k,k) for n>=0 (conjecture).
PROG
(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))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 08 2006
STATUS
approved