OFFSET
0,4
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..500
MAPLE
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(b(n-i*j, i-1)*j!*(-1)^j, j=0..min(4, n/i))))
end:
a:= n-> b(n$2):
seq(a(n), n=0..60); # Alois P. Heinz, Oct 04 2017
PROG
(PARI) Vec(prod(m=1, 50, 1+sum(k=1, 4, (-1)^k*k!*x^(k*m))) + O(x^50)) \\ Michel Marcus, Oct 04 2017
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Oct 04 2017
STATUS
approved