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 | 126 |
| 2 | 43848 |
| 3 | 17653104 |
| 4 | 7691658282 |
| 5 | 3503623887792 |
| 6 | 1642412452485168 |
| 7 | 785518220230462656 |
| 8 | 381292445408455002744 |
| 9 | 187197126720396903747630 |
| 10 | 92737188888575341959000432 |
| 11 | 46279260465924099748796201232 |
| 12 | 23235412441447288670723222759280 |