OFFSET
0,4
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..300
H. S. Wilf, Generatingfunctionology, 2nd edn., Academic Press, NY, 1994, Theorem 4.8.2.
MAPLE
with(combinat): with(numtheory): with(padic):
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0, add(
`if`(irem(j, mul(p^ordp(10, p), p=factorset(i)))=0, (i-1)!^j*
multinomial(n, n-i*j, i$j)/j!*b(n-i*j, i-1), 0), j=0..n/i)))
end:
a:= n-> b(n$2):
seq(a(n), n=0..25);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 09 2014
STATUS
approved