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 | 7 |
| 3 | 25 |
| 4 | 92 |
| 5 | 344 |
| 6 | 1300 |
| 7 | 4950 |
| 8 | 18955 |
| 9 | 72905 |
| 10 | 281403 |
| 11 | 1089343 |
| 12 | 4227273 |
| 13 | 16438345 |
| 14 | 64037453 |
| 15 | 249855417 |
| 16 | 976205516 |
| 17 | 3818779616 |
| 18 | 14954876080 |
| 19 | 58623077586 |
| 20 | 230007291334 |
| 21 | 903164858092 |
| 22 | 3549071519462 |
| 23 | 13955918890440 |
| 24 | 54912972103772 |
| 25 | 216194101316654 |
| 26 | 851622127750060 |