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 | 1 |
| 10 | 3 |
| 11 | 9 |
| 12 | 28 |
| 13 | 92 |
| 14 | 324 |
| 15 | 1217 |
| 16 | 4871 |
| 17 | 20703 |
| 18 | 93166 |
| 19 | 442542 |
| 20 | 2212711 |
| 21 | 11616735 |
| 22 | 63892044 |
| 23 | 367379253 |
| 24 | 2204275523 |
| 25 | 13776722023 |
| 26 | 89548693155 |
| 27 | 604453678799 |
| 28 | 4231175751597 |
| 29 | 30676024199079 |
| 30 | 230070181493096 |
| 31 | 1783043906571497 |
| 32 | 14264351252571976 |