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 | 3 |
| 3 | 22 |
| 4 | 269 |
| 5 | 4616 |
| 6 | 102847 |
| 7 | 2824816 |
| 8 | 92355769 |
| 9 | 3506278528 |
| 10 | 151720849691 |
| 11 | 7375146930944 |
| 12 | 398113181435653 |
| 13 | 23640909385071616 |
| 14 | 1532325553233566743 |
| 15 | 107698939845869111296 |
| 16 | 8162300091585206125553 |
| 17 | 663836705760309127184384 |