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 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 19 |
| 5 | 52 |
| 6 | 172 |
| 7 | 550 |
| 8 | 1782 |
| 9 | 5845 |
| 10 | 18508 |
| 11 | 56345 |
| 12 | 164157 |
| 13 | 454518 |
| 14 | 1196924 |
| 15 | 3003750 |
| 16 | 7198311 |
| 17 | 16523847 |
| 18 | 36447873 |
| 19 | 77478005 |
| 20 | 159172517 |
| 21 | 316874035 |
| 22 | 612729396 |
| 23 | 1153359711 |
| 24 | 2117566545 |
| 25 | 3798941401 |
| 26 | 6670327291 |
| 27 | 11479693332 |
| 28 | 19390588953 |
| 29 | 32185179449 |
| 30 | 52553840336 |