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 | 9 |
| 3 | 190 |
| 4 | 5705 |
| 5 | 204876 |
| 6 | 8209278 |
| 7 | 354331692 |
| 8 | 16140234825 |
| 9 | 765868074400 |
| 10 | 37525317999884 |
| 11 | 1886768082651816 |
| 12 | 96906387191038334 |
| 13 | 5066711735118128200 |
| 14 | 268954195756648761900 |
| 15 | 14464077426547576156440 |
| 16 | 786729115199980286001225 |
| 17 | 43219452658242723841261800 |