OFFSET
0,6
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..386
FORMULA
a(n) ~ (exp(1) - 2*exp(4/3) - 2*exp(3/2) + 4*exp(2)) * n^(n-1). - Vaclav Kotesovec, Aug 18 2017
MAPLE
b:= proc(n, m) option remember; (k-> `if`(m>k, 0,
`if`(n=0, `if`(m=k, 1, 0), add(b(n-j, ilcm(m, j))
*binomial(n-1, j-1)*(j-1)!, j=1..n))))(6)
end:
a:= n-> add(b(j, 1)*n^(n-j)*binomial(n-1, j-1), j=0..n):
seq(a(n), n=0..22);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Aug 17 2017
STATUS
approved