A072881 - cp's OEIS frontend

A072881 a(1)=a(2)=a(3)=1; for n>3, a(n)=(a(n-1)*a(n-2)+a(n-1)+a(n-2))/a(n-3).

n	a(n)
1	1
2	1
3	1
4	3
5	7
6	31
7	85
8	393
9	1093
10	5071
11	14119
12	65523
13	182449
14	846721
15	2357713
16	10941843
17	30467815
18	141397231
19	393723877
20	1827222153
21	5087942581
22	23612490751
23	65749529671
24	305135157603
25	849655943137
26	3943144558081

[1, 1, 1, 3, 7, 31, 85, 393, 1093, 5071, 14119, 65523, 182449, 846721, 2357713, 10941843, 30467815, 141397231, 393723877, 1827222153, 5087942581, 23612490751, 65749529671, 305135157603, 849655943137, 3943144558081]

cp's OEIS Frontend

A072881 a(1)=a(2)=a(3)=1; for n>3, a(n)=(a(n-1)*a(n-2)+a(n-1)+a(n-2))/a(n-3).

Table of values

List of values