A268218 - cp's OEIS frontend

A268218 a(n) = (n!/3!)*Sum(1/k!,k=1..n-3).

n	a(n)
0	0
1	0
2	0
3	0
4	4
5	30
6	200
7	1435
8	11536
9	103908
10	1039200
11	11431365
12	137176600
13	1783296086
14	24966145568
15	374492183975
16	5991874944160
17	101861874051400
18	1833513732926016
19	34836760925595273
20	696735218511906600
21	14631439588750039930
22	321891670952500880000
23	7403508431907520241771

[0, 0, 0, 0, 4, 30, 200, 1435, 11536, 103908, 1039200, 11431365, 137176600, 1783296086, 24966145568, 374492183975, 5991874944160, 101861874051400, 1833513732926016, 34836760925595273, 696735218511906600, 14631439588750039930, 321891670952500880000, 7403508431907520241771]

cp's OEIS Frontend

A268218 a(n) = (n!/3!)*Sum(1/k!,k=1..n-3).

Table of values

List of values