This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 24 |
| 7 | 60 |
| 8 | 152 |
| 9 | 386 |
| 10 | 980 |
| 11 | 2488 |
| 12 | 6324 |
| 13 | 16098 |
| 14 | 41032 |
| 15 | 104711 |
| 16 | 267512 |
| 17 | 684138 |
| 18 | 1751316 |
| 19 | 4487217 |
| 20 | 11506792 |
| 21 | 29530524 |
| 22 | 75841152 |
| 23 | 194910254 |
| 24 | 501234960 |
| 25 | 1289755668 |
| 26 | 3320603016 |
| 27 | 8553723949 |
| 28 | 22044934324 |
| 29 | 56841474482 |
| 30 | 146626826376 |
| 31 | 378392593206 |
| 32 | 976884539336 |
| 33 | 2522936490418 |