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A291214 Column 2 of triangle A290580. 3

%I

%S 1,112,5868,250128,10020912,399379728,16255733440,684615750832,

%T 30031767680256,1376568893633760,66017645596167168,

%U 3313241694194681184,173934275433107845120,9543378596912872361440,546711252967087466397696,32663132242303127521217184

%N Column 2 of triangle A290580.

%H Vaclav Kotesovec, <a href="/A291214/b291214.txt">Table of n, a(n) for n = 1..77</a>

%F a(n) ~ c * n^(n+5), where c = (exp(1) + 8*exp(3) + 14*exp(5) - 8*exp(7) + exp(9))/512 = 3.06876067343310165753640903985063833178947434...

%o (PARI) /* As column 2 of triangle A290580 */

%o { A290580(n, k) = my(W=1, E=1, S=x, C=1, D=1); for(i=0, n,

%o S = intformal(C*D +x*O(x^n)) ;

%o C = 1 - intformal(S*D) ; D = 1 - m*intformal(S*C) ;

%o E = subst( (1 + S)/C, m, 1-m) ) ;

%o for(i=0, n, W = subst(E, x, x*W));

%o n!*polcoeff(polcoeff(W, n, x), k, m) }

%o for(n=1, 25, print1( A290580(n+4, 2), ", ")) \\ after _Paul D. Hanna_

%Y Cf. A290580, A290581.

%K nonn

%O 1,2

%A _Vaclav Kotesovec_, Aug 21 2017

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Last modified August 24 02:32 EDT 2019. Contains 326260 sequences. (Running on oeis4.)