|
|
A363010
|
|
a(n) = n! * [x^n] 1/(1 - f^n(x)), where f(x) = exp(x) - 1.
|
|
2
|
|
|
1, 1, 4, 36, 594, 15775, 618838, 33757864, 2448904188, 228290728635, 26617527649365, 3797508644987398, 651082351708066303, 132130157056046918808, 31333332827346731906130, 8587011712002719806274022, 2693586800519167315881703732, 958983405298849163873718493941
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
FORMULA
|
a(n) = T(n,n), T(n,k) = Sum_{j=0..n} Stirling2(n,j) * T(j,k-1), k>1, T(n,0) = n!.
|
|
MAPLE
|
b:= proc(n, t, m) option remember; `if`(n=0, `if`(t<2, m!,
b(m, t-1, 0)), m*b(n-1, t, m)+b(n-1, t, m+1))
end:
a:= n-> b(n$2, 0):
|
|
CROSSREFS
|
Main diagonal of A153278 (for n>=1).
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|