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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 1 |
| 11 | 55 |
| 12 | 1705 |
| 13 | 39325 |
| 14 | 752752 |
| 15 | 12662650 |
| 16 | 193754990 |
| 17 | 2758334150 |
| 18 | 37112163803 |
| 19 | 477297033785 |
| 20 | 5917585057033 |
| 21 | 71187151690655 |
| 22 | 835145968875284 |
| 23 | 9593573078823360 |
| 24 | 108264887496309962 |
| 25 | 1203738001326003000 |
| 26 | 13226402531839795155 |