|
|
A350268
|
|
a(n) = Sum_{k=0..n} (n - k)! * (n - 1)^k. Row sums of A350269.
|
|
1
|
|
|
1, 1, 4, 22, 168, 1720, 22670, 368784, 7134148, 159416704, 4027395330, 113235212800, 3501763366904, 118024658758656, 4303855119215782, 168777440194263040, 7081468496171815500, 316501174908316647424, 15010862087643791689322, 752916261526858377363456
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
MATHEMATICA
|
a[1] = 1; a[n_] := Sum[(n - k)! * (n - 1)^k, {k, 0, n}]; Array[a, 20, 0] (* Amiram Eldar, Dec 25 2021 *)
|
|
PROG
|
(PARI) a(n) = sum(k=0, n, (n-k)!*(n-1)^k); \\ Michel Marcus, Dec 25 2021
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|