OFFSET
1,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..300
FORMULA
E.g.f.: Sum(x^n/(n!+x^n),n=1..inf)*Product(1+x^n/n!,n=1..inf).
MAPLE
A131623 := proc(n) local su, i ; su := add(x^i/(i!+x^i), i=1..n+1) ; for i from 1 to n do su := taylor(su*(1+x^i/i!), x=0, n+1) ; od: n!*coeftayl(su, x=0, n) ; end: seq(A131623(n), n=1..30) ; # R. J. Mathar, Oct 25 2007
MATHEMATICA
nn=20; p=Product[1+y x^i/i!, {i, 1, nn}]; Range[0, nn]! CoefficientList[Series[D[p, y]/.y->1, {x, 0, nn}], x] (* Geoffrey Critzer, Aug 30 2012 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Sep 02 2007
EXTENSIONS
More terms from R. J. Mathar, Oct 25 2007
STATUS
approved