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 | 4 |
| 3 | 39 |
| 4 | 862 |
| 5 | 35775 |
| 6 | 2406208 |
| 7 | 238773109 |
| 8 | 32867762616 |
| 9 | 6009498859909 |
| 10 | 1412846181645855 |
| 11 | 416415343791239162 |
| 12 | 150747204270574506888 |
| 13 | 65905473934553360340713 |
| 14 | 34305461329980340135062217 |
| 15 | 21003556204331356488142290707 |
| 16 | 14967168378184553824642693791437 |