login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

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 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)

A221681 as a simple table

n a(n)
1 0
2 2
3 5
4 38
5 166
6 891
7 4326
8 21985
9 109567
10 551027
11 2759757
12 13846871
13 69418237
14 348143326
15 1745704167
16 8754189034
17 43898170484
18 220132165897
19 1103869189670
20 5535451646119
21 27757983230949
22 139194805502163
23 698004183274703

[0,2,5,38,166,891,4326,21985,109567,551027,
 2759757,13846871,69418237,348143326,1745704167,
 8754189034,43898170484,220132165897,1103869189670,
 5535451646119,27757983230949,139194805502163,
 698004183274703]

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 26 21:15 EST 2022. Contains 358362 sequences. (Running on oeis4.)