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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 16 |
| 5 | 121 |
| 6 | 1480 |
| 7 | 50993 |
| 8 | 3279685 |
| 9 | 505641590 |
| 10 | 152461906778 |
| 11 | 103587671805408 |
| 12 | 145528904385412088 |
| 13 | 442626996609870050404 |
| 14 | 2918362542591139744394993 |
| 15 | 40446812392580562094804791143 |
| 16 | 1260273961234324967695235253182680 |
| 17 | 80686628450087709982052029871655471264 |