OFFSET
0,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..200
FORMULA
a(n) = n! * [x^n] (exp(x)-x^4/4!)^n.
MAPLE
b:= proc(n, i) option remember; `if`(n=0 and i=0, 1, `if`(i<1, 0,
add(`if`(j=4, 0, b(n-j, i-1) *binomial(n, j)), j=0..n)))
end:
a:= n-> b(n$2):
seq(a(n), n=0..25);
MATHEMATICA
Table[n!*SeriesCoefficient[(E^x-x^4/4!)^n, {x, 0, n}], {n, 0, 20}] (* Vaclav Kotesovec, Jul 23 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jul 21 2014
STATUS
approved