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A291214 Column 2 of triangle A290580. 3
1, 112, 5868, 250128, 10020912, 399379728, 16255733440, 684615750832, 30031767680256, 1376568893633760, 66017645596167168, 3313241694194681184, 173934275433107845120, 9543378596912872361440, 546711252967087466397696, 32663132242303127521217184 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 1..77

FORMULA

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

PROG

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

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

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

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

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

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

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

for(n=1, 25, print1( A290580(n+4, 2), ", ")) \\ after Paul D. Hanna

CROSSREFS

Cf. A290580, A290581.

Sequence in context: A265660 A271032 A213803 * A035813 A223613 A075910

Adjacent sequences:  A291211 A291212 A291213 * A291215 A291216 A291217

KEYWORD

nonn

AUTHOR

Vaclav Kotesovec, Aug 21 2017

STATUS

approved

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Last modified July 22 10:03 EDT 2019. Contains 325219 sequences. (Running on oeis4.)