A333139 - 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

A333139 as a simple table

n	a(n)
1	220
2	4220
3	25220
4	84280
5	217800
6	456640
7	873090
8	1501520
9	2436020
10	3736540
11	5523970
12	7830800
13	10879460
14	14665340
15	19398660
16	25173960
17	32203320
18	40502280
19	50458120
20	61995140
21	75517160

[220,4220,25220,84280,217800,456640,873090, 1501520,2436020,3736540,5523970,7830800,10879460, 14665340,19398660,25173960,32203320,40502280, 50458120,61995140,75517160]