A230021 - 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

A230021 as a simple table

n	a(n)
1	21
2	291
3	2991
4	43954
5	211552
6	439954
7	43564354
8	43999954
9	464057476
10	43999999954
11	435600004354
12	439560043954
13	439999999954

[21,291,2991,43954,211552,439954,43564354, 43999954,464057476,43999999954,435600004354, 439560043954,439999999954]