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 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 17 |
| 5 | 50 |
| 6 | 147 |
| 7 | 434 |
| 8 | 1282 |
| 9 | 3789 |
| 10 | 11200 |
| 11 | 33109 |
| 12 | 97878 |
| 13 | 289354 |
| 14 | 855413 |
| 15 | 2528850 |
| 16 | 7476023 |
| 17 | 22101326 |
| 18 | 65338038 |
| 19 | 193158521 |
| 20 | 571033600 |
| 21 | 1688143881 |
| 22 | 4990651642 |
| 23 | 14753839486 |
| 24 | 43616704857 |
| 25 | 128943855250 |
| 26 | 381196100507 |
| 27 | 1126928202714 |
| 28 | 3331532438042 |
| 29 | 9848993360069 |