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 A185756 Column 1 of triangle A185755. 4
 2, 15, 154, 1995, 31191, 571221, 11992688, 283976517, 7487521975, 217567092743, 6907888374828, 237951469523807, 8838510559556783, 352160268261051113, 14982705940607112640, 677935029521206050505, 32508195354031791206799 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 0 of triangle A185755 equals n^(n-1). A185755(n,k) equals the coefficient of x^n*y^k in the n-th iteration of x*(1+xy)/(1-x). LINKS PROG (PARI) {a(n)=local(A=x, G=x*(1+x*y)/(1-x)); for(i=1, n+1, A=subst(G, x, A+O(x^(n+2)))); polcoeff(polcoeff(A, n+1, x), 1, y)} CROSSREFS Cf. A185755, A185757, A185758, A185759. Sequence in context: A060226 A002103 A191364 * A124548 A139085 A204679 Adjacent sequences:  A185753 A185754 A185755 * A185757 A185758 A185759 KEYWORD nonn AUTHOR Paul D. Hanna, Feb 03 2011 STATUS approved

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Last modified May 26 04:23 EDT 2013. Contains 225653 sequences.