A268220 - cp's OEIS frontend

A268220 a(n) = (n!/5!)*Sum(1/k!,k=1..n-5).

n	a(n)
0	0
1	0
2	0
3	0
4	0
5	0
6	6
7	63
8	560
9	5166
10	51912
11	571494
12	6858720
13	89164647
14	1248307060
15	18724608903
16	299593746816
17	5093093702060
18	91675686645648
19	1741838046278940
20	34836760925594304
21	731571979437500733
22	16094583547625042460
23	370175421595376010229
24	8884210118289024288000

[0, 0, 0, 0, 0, 0, 6, 63, 560, 5166, 51912, 571494, 6858720, 89164647, 1248307060, 18724608903, 299593746816, 5093093702060, 91675686645648, 1741838046278940, 34836760925594304, 731571979437500733, 16094583547625042460, 370175421595376010229, 8884210118289024288000]

cp's OEIS Frontend

A268220 a(n) = (n!/5!)*Sum(1/k!,k=1..n-5).

Table of values

List of values