A291856 - cp's OEIS frontend

A291856 a(0) = -1, a(1) = 1, a(n) = a(n-1) + (n-1)*a(n-2) for n > 1.

n	a(n)
0	-1
1	1
2	0
3	2
4	2
5	10
6	20
7	80
8	220
9	860
10	2840
11	11440
12	42680
13	179960
14	734800
15	3254240
16	14276240
17	66344080
18	309040160
19	1503233600
20	7374996640
21	37439668640
22	192314598080
23	1015987308160
24	5439223064000
25	29822918459840
26	165803495059840
27	941199375015680

[-1, 1, 0, 2, 2, 10, 20, 80, 220, 860, 2840, 11440, 42680, 179960, 734800, 3254240, 14276240, 66344080, 309040160, 1503233600, 7374996640, 37439668640, 192314598080, 1015987308160, 5439223064000, 29822918459840, 165803495059840, 941199375015680]

cp's OEIS Frontend

A291856 a(0) = -1, a(1) = 1, a(n) = a(n-1) + (n-1)*a(n-2) for n > 1.

Table of values

List of values