A121253 - cp's OEIS frontend

A121253 a(n) = a(n-1)*a(n-3)+1 with a(0)=a(1)=a(2)=0.

n	a(n)
0	0
1	0
2	0
3	1
4	1
5	1
6	2
7	3
8	4
9	9
10	28
11	113
12	1018
13	28505
14	3221066
15	3279045189
16	93469183112446
17	301070407771273987437
18	987223472152664180906141290594
19	92274971491542102812339702600558728264132925

[0, 0, 0, 1, 1, 1, 2, 3, 4, 9, 28, 113, 1018, 28505, 3221066, 3279045189, 93469183112446, 301070407771273987437, 987223472152664180906141290594, 92274971491542102812339702600558728264132925]

cp's OEIS Frontend

A121253 a(n) = a(n-1)*a(n-3)+1 with a(0)=a(1)=a(2)=0.

Table of values

List of values