A214916 - cp's OEIS frontend

A214916 a(0) = a(1) = 1, a(n) = n! / a(n-2).

n	a(n)
0	1
1	1
2	2
3	6
4	12
5	20
6	60
7	252
8	672
9	1440
10	5400
11	27720
12	88704
13	224640
14	982800
15	5821200
16	21288960
17	61102080
18	300736800
19	1990850400
20	8089804800
21	25662873600
22	138940401600
23	1007370302400
24	4465572249600
25	15397724160000
26	90311261040000
27	707173952284800
28	3375972620697600

[1, 1, 2, 6, 12, 20, 60, 252, 672, 1440, 5400, 27720, 88704, 224640, 982800, 5821200, 21288960, 61102080, 300736800, 1990850400, 8089804800, 25662873600, 138940401600, 1007370302400, 4465572249600, 15397724160000, 90311261040000, 707173952284800, 3375972620697600]

cp's OEIS Frontend

A214916 a(0) = a(1) = 1, a(n) = n! / a(n-2).

Table of values

List of values