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A124528
a(n) = Sum_{k=0..n} 2^k*A124526(n,k) for n>=0.
3
1, 1, 3, 8, 26, 94, 377, 1639, 7623, 38034, 199338, 1111816, 6442481, 39478219, 249507483, 1659172454, 11321526022, 80944313164, 591617080305, 4514822914133, 35120998653271, 284407875530728, 2342407874087454
OFFSET
0,3
PROG
(PARI) {a(n)=sum(k=0, n\2, 2^k*(n\2)!*((n+1)\2)!*polcoeff(polcoeff(exp((1+y)*(exp(x+x*O(x^n))-1)), n\2), k) *polcoeff(polcoeff(exp((1+y)*(exp(x+x*O(x^n))-1)), (n+1)\2), k))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 08 2006
STATUS
approved