A000255 - cp's OEIS frontend

A000255 a(n) = na(n-1) + (n-1)a(n-2), a(0) = 1, a(1) = 1.

n	a(n)
0	1
1	1
2	3
3	11
4	53
5	309
6	2119
7	16687
8	148329
9	1468457
10	16019531
11	190899411
12	2467007773
13	34361893981
14	513137616783
15	8178130767479
16	138547156531409
17	2486151753313617
18	47106033220679059
19	939765362752547227
20	19690321886243846661
21	432292066866171724421

[1, 1, 3, 11, 53, 309, 2119, 16687, 148329, 1468457, 16019531, 190899411, 2467007773, 34361893981, 513137616783, 8178130767479, 138547156531409, 2486151753313617, 47106033220679059, 939765362752547227, 19690321886243846661, 432292066866171724421]

cp's OEIS Frontend

A000255 a(n) = na(n-1) + (n-1)a(n-2), a(0) = 1, a(1) = 1.

Table of values

List of values

cp's OEIS Frontend

A000255 a(n) = n*a(n-1) + (n-1)*a(n-2), a(0) = 1, a(1) = 1.

Table of values

List of values

A000255 a(n) = na(n-1) + (n-1)a(n-2), a(0) = 1, a(1) = 1.