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A293720 E.g.f.: exp(x + 4*x^2). 2
1, 1, 9, 25, 241, 1041, 10681, 60649, 658785, 4540321, 51972841, 415198521, 4988808529, 44847866545, 563683953561, 5586645006601, 73228719433921, 788319280278849, 10747425123292105, 124265401483446361, 1757874020223846321, 21640338257575264081 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..612

FORMULA

a(n) ~ 2^((3*n-1)/2) * exp(-1/32 + sqrt(2*n)/4 - n/2) * n^(n/2). - Vaclav Kotesovec, Oct 15 2017

MATHEMATICA

CoefficientList[Series[E^(x + 4*x^2), {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Oct 15 2017 *)

PROG

(PARI) N=66; x='x+O('x^N); Vec(serlaplace(exp(x+4*x^2)))

CROSSREFS

Column k=2 of A293724.

Sequence in context: A053929 A014760 A013397 * A227891 A193065 A278911

Adjacent sequences:  A293717 A293718 A293719 * A293721 A293722 A293723

KEYWORD

nonn

AUTHOR

Seiichi Manyama, Oct 15 2017

STATUS

approved

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Last modified September 18 06:42 EDT 2021. Contains 347510 sequences. (Running on oeis4.)