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 | 2 |
| 2 | 5 |
| 3 | 16 |
| 4 | 57 |
| 5 | 206 |
| 6 | 737 |
| 7 | 2612 |
| 8 | 9213 |
| 9 | 32442 |
| 10 | 114205 |
| 11 | 402072 |
| 12 | 1415713 |
| 13 | 4985126 |
| 14 | 17554489 |
| 15 | 61816252 |
| 16 | 217679141 |
| 17 | 766531986 |
| 18 | 2699251381 |
| 19 | 9505089568 |
| 20 | 33471028105 |
| 21 | 117864194430 |
| 22 | 415044573969 |
| 23 | 1461529529924 |
| 24 | 5146600421325 |