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 | 6 |
| 3 | 45 |
| 4 | 452 |
| 5 | 5725 |
| 6 | 87704 |
| 7 | 1577849 |
| 8 | 32618512 |
| 9 | 762046137 |
| 10 | 19856872032 |
| 11 | 571007744549 |
| 12 | 17962793210944 |
| 13 | 613650073693397 |
| 14 | 22624291883495808 |
| 15 | 895379458590349425 |
| 16 | 37861032312753094912 |
| 17 | 1703550488551604490353 |