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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 6 |
| 4 | 11 |
| 5 | 36 |
| 6 | 85 |
| 7 | 235 |
| 8 | 600 |
| 9 | 1590 |
| 10 | 4140 |
| 11 | 10866 |
| 12 | 28416 |
| 13 | 74431 |
| 14 | 194821 |
| 15 | 510096 |
| 16 | 1335395 |
| 17 | 3496170 |
| 18 | 9153025 |
| 19 | 23963005 |
| 20 | 62735880 |
| 21 | 164244756 |
| 22 | 429998256 |
| 23 | 1125750156 |
| 24 | 2947252056 |
| 25 | 7716006181 |
| 26 | 20200766305 |
| 27 | 52886292930 |
| 28 | 138458112275 |
| 29 | 362488044120 |