A009799 E.g.f. tanh(sin(x)*exp(x)).

0, 1, 2, 0, -24, -148, -248, 5488, 73024, 346768, -3749728, -100273536, -922745472, 4147334336, 283697686144, 4362058183936, 4465927211008, -1382047649378048, -33554250522144256, -226963355560685568, 10084981854738991104

Offset

0,3

Links

Table of n, a(n) for n=0..20.

Formula

a(n)=sum(m=1..n, ((sum(k=1..m, (-1)^(k+1)*k!*2^(1-k)*stirling2(m,k)))*sum(j=0..(n-m)/2, binomial(n,2*j+m)*(m^(n-2*j-m)*sum(i=0..m/2, (2*i-m)^(2*j+m)*(-1)^(m+j-i)*binomial(m,i))) ))/(m!)). - Vladimir Kruchinin, Jun 30 2011

Prog

(Maxima)
a(n):=sum(((sum((-1)^(k+1)*k!*2^(1-k)*stirling2(m, k), k, 1, m))*sum(binomial(n, 2*j+m)*(m^(n-2*j-m)*sum((2*i-m)^(2*j+m)*(-1)^(m+j-i)*binomial(m, i), i, 0, m/2)), j, 0, (n-m)/2 ))/(m!), m, 1, n); /* Vladimir Kruchinin Jun 30 2011 */

Crossrefs

Sequence in context: A012290 A012591 A319221 * A109582 A375609 A308506

Adjacent sequences: A009796 A009797 A009798 * A009800 A009801 A009802

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved