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 | 13 |
| 2 | 469 |
| 3 | 21400 |
| 4 | 1065229 |
| 5 | 55778797 |
| 6 | 3020636341 |
| 7 | 167544629317 |
| 8 | 9461343754981 |
| 9 | 541786421337805 |
| 10 | 31372013730812824 |
| 11 | 1833216802356228733 |
| 12 | 107939805322734748117 |
| 13 | 6396432908013911687437 |
| 14 | 381139174656828902370421 |
| 15 | 22819171231066917509661277 |