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 | 5 |
| 4 | 15 |
| 5 | 50 |
| 6 | 177 |
| 7 | 649 |
| 8 | 2437 |
| 9 | 9322 |
| 10 | 36214 |
| 11 | 142546 |
| 12 | 567409 |
| 13 | 2280246 |
| 14 | 9238883 |
| 15 | 37699021 |
| 16 | 154783906 |
| 17 | 638983998 |
| 18 | 2650697658 |
| 19 | 11043733080 |
| 20 | 46192300706 |
| 21 | 193892210528 |
| 22 | 816486626337 |
| 23 | 3448376227978 |
| 24 | 14603301098654 |
| 25 | 61996178908151 |