A186739 - cp's OEIS frontend

A186739 a(0)=0, a(1)=0; for n>1, a(n) = a(n-1) + (n-2)*a(n-2) + 1.

n	a(n)
0	0
1	0
2	1
3	2
4	5
5	12
6	33
7	94
8	293
9	952
10	3297
11	11866
12	44837
13	175364
14	713409
15	2993142
16	12980869
17	57878000
18	265571905
19	1249497906
20	6029792197
21	29770252412
22	150366096353
23	775541397006
24	4083595516773
25	21921047647912
26	119927340050465
27	667953531248266
28	3786064372560357

[0, 0, 1, 2, 5, 12, 33, 94, 293, 952, 3297, 11866, 44837, 175364, 713409, 2993142, 12980869, 57878000, 265571905, 1249497906, 6029792197, 29770252412, 150366096353, 775541397006, 4083595516773, 21921047647912, 119927340050465, 667953531248266, 3786064372560357]

cp's OEIS Frontend

A186739 a(0)=0, a(1)=0; for n>1, a(n) = a(n-1) + (n-2)*a(n-2) + 1.

Table of values

List of values