A009813 - 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

A009813 as a simple table

n	a(n)
0	1
1	3
2	17
3	147
4	3265
5	248259
6	25402769
7	2697740307
8	299763466753
9	36321927229443
10	5149754111041937
11	933794260030934547
12	223162280662322953153
13	65749433548871560459971

[1,3,17,147,3265,248259,25402769,2697740307, 299763466753,36321927229443,5149754111041937, 933794260030934547,223162280662322953153, 65749433548871560459971]