A191462 E.g.f. (1+x)^(1+x^2+x^4)

1, 1, 0, 6, 12, 100, 780, -1092, 43344, 48816, 1264320, 24662880, -162851040, 4327633440, -17686783296, 275230488960, 3743721112320, -70886371933440, 2127136959383040, -25991855154846720, 402985066993459200

Offset

0,4

Links

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

Formula

a(n)=sum(k=1..n, sum(i=0..(n-k)/2, ((sum(j=0..k, binomial(j,i-j)*binomial(k,j)))*stirling1(n-2*i,k))/(n-2*i)!)), n>0, a(0)=1.

Mathematica

With[{nn=20}, CoefficientList[Series[(1+x)^(1+x^2+x^4), {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Aug 24 2012 *)

Prog

(Maxima)
a(n):=sum(sum(((sum(binomial(j, i-j)*binomial(k, j), j, 0, k))*stirling1(n-2*i, k))/(n-2*i)!, i, 0, (n-k)/2), k, 1, n);

Crossrefs

Sequence in context: A002898 A003613 A099767 * A340060 A080450 A144760

Adjacent sequences: A191459 A191460 A191461 * A191463 A191464 A191465

Keyword

sign

Author

Vladimir Kruchinin, Jun 02 2011

Status

approved