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A371018
Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + x^2*exp(x)) ).
3
1, 0, 2, 6, 60, 620, 7950, 129402, 2365496, 50512968, 1208642490, 32223422990, 947694971652, 30435132773916, 1061061668979494, 39889366397571810, 1608910488000292080, 69305890226183224592, 3175519952912430375666, 154216789672147809137046
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OFFSET
0,3
LINKS
Table of n, a(n) for n=0..19.
Index entries for reversions of series
FORMULA
a(n) = (n!/(n+1)) * Sum_{k=0..floor(n/2)} k^(n-2*k) * binomial(n+1,k)/(n-2*k)!.
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(serreverse(x/(1+x^2*exp(x)))/x))
(PARI) a(n) = n!*sum(k=0, n\2, k^(n-2*k)*binomial(n+1, k)/(n-2*k)!)/(n+1);
CROSSREFS
Cf.
A161633
,
A371019
.
Cf.
A365283
.
Sequence in context:
A356259
A215720
A376492
*
A376476
A211936
A156972
Adjacent sequences:
A371015
A371016
A371017
*
A371019
A371020
A371021
KEYWORD
nonn
AUTHOR
Seiichi Manyama
, Mar 08 2024
STATUS
approved