OFFSET
0,2
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 0..240
FORMULA
a(n) = Sum_(m=0..2*n, binomial(2*n,m)*Sum_(k=0..2*n-2*m, binomial(k+m-1,m-1)*(k+m)!*(-1)^(k)*2^(2*n-2*m-k)*stirling2(2*n-m,k+m))), n>0, a(0)=1. - Vladimir Kruchinin, Jun 06 2011
MATHEMATICA
nmax = 20; Table[(CoefficientList[Series[E^(x*Tanh[x]), {x, 0, 2*nmax}], x]*Range[0, 2*nmax]!)[[k]], {k, 1, 2*nmax, 2}] (* Vaclav Kotesovec, May 24 2022 *)
PROG
(Maxima)
a(n):=sum(binomial(2*n, m)*sum(binomial(k+m-1, m-1)*(k+m)!*(-1)^(k)*2^(2*n-2*m-k)*stirling2(2*n-m, k+m), k, 0, 2*n-2*m), m, 0, 2*n); /* Vladimir Kruchinin, Jun 06 2011 */
CROSSREFS
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
More terms from Vaclav Kotesovec, May 25 2022
STATUS
approved