A208990 - 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

A208990 as a simple table

n	a(n)
1	1
2	3
3	11
4	58
5	351
6	2354
7	16307
8	116183
9	843779
10	6227718
11	46571177
12	352155364
13	2688196663
14	20688930990
15	160363122189

[1,3,11,58,351,2354,16307,116183,843779,6227718, 46571177,352155364,2688196663,20688930990, 160363122189]