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A293720 E.g.f.: exp(x + 4*x^2). 2

%I

%S 1,1,9,25,241,1041,10681,60649,658785,4540321,51972841,415198521,

%T 4988808529,44847866545,563683953561,5586645006601,73228719433921,

%U 788319280278849,10747425123292105,124265401483446361,1757874020223846321,21640338257575264081

%N E.g.f.: exp(x + 4*x^2).

%H Seiichi Manyama, <a href="/A293720/b293720.txt">Table of n, a(n) for n = 0..612</a>

%F a(n) ~ 2^((3*n-1)/2) * exp(-1/32 + sqrt(2*n)/4 - n/2) * n^(n/2). - _Vaclav Kotesovec_, Oct 15 2017

%t CoefficientList[Series[E^(x + 4*x^2), {x, 0, 20}], x] * Range[0, 20]! (* _Vaclav Kotesovec_, Oct 15 2017 *)

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

%Y Column k=2 of A293724.

%K nonn

%O 0,3

%A _Seiichi Manyama_, Oct 15 2017

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Last modified October 23 00:39 EDT 2021. Contains 348211 sequences. (Running on oeis4.)