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A126340
Largest coefficient of q in { [x^n] W(x,q) } where W(x,q) = exp( q*x*W(q*x,q) ); largest term in rows of triangle A126265.
0
1, 1, 2, 6, 28, 245, 2100, 26502, 371616, 6565104, 125017200, 2888063640, 71356079520, 2012272702440, 60689867021784, 2032123676705850, 72464991800160960, 2806386304260520800, 115406148262413677760
OFFSET
0,3
EXAMPLE
a(n) appears to be divisible by n for n>0:
a(n)/n = [1,1,2,7,49,350,3786,46452,729456,12501720,262551240,...].
PROG
(PARI) {a(n)=local(W=1+x, V, H); for(i=0, n, W=exp(subst(x*W, x, q*x+x*O(x^n)))); V=Vec(Vec(W)[n+1]*n!+O(q^(n*(n+1)/2+1))); H=0; for(k=1, #V, if(V[k]>H, H=V[k])); H}
CROSSREFS
Cf. A126265.
Sequence in context: A377132 A355208 A002047 * A370423 A355768 A277480
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 25 2006
STATUS
approved