A203269 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give

A203269 as a simple table

n	a(n)
0	1
1	2
2	8
3	4
4	132
5	24
6	1556
7	88
8	5364
9	168
10	5612
11	136
12	1128168
13	28656
14	86804
15	1672
16	3434920
17	48080
18	173886368
19	2462176
20	4093653652
21	62126504
22	4292224444
23	10991336
24	182512332988
25	4948498616

[1,2,8,4,132,24,1556,88,5364,168,5612,136,1128168, 28656,86804,1672,3434920,48080,173886368,2462176, 4093653652,62126504,4292224444,10991336, 182512332988,4948498616]