A147189 - 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

A147189 as a simple table

n	a(n)
1	1
2	1
3	1
4	1
5	1
6	1
7	1
8	1
9	3
10	5
11	11
12	19
13	53
14	119
15	315
16	741
17	2791
18	8507
19	37441
20	131241
21	690373
22	2947311
23	17685311
24	87080583
25	622517947
26	3695889011
27	31549600531

[1,1,1,1,1,1,1,1,3,5,11,19,53,119,315,741,2791, 8507,37441,131241,690373,2947311,17685311, 87080583,622517947,3695889011,31549600531]