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 | 8 |
| 2 | 61 |
| 3 | 450 |
| 4 | 3240 |
| 5 | 22896 |
| 6 | 159408 |
| 7 | 1096416 |
| 8 | 7464960 |
| 9 | 50388480 |
| 10 | 337602816 |
| 11 | 2247326208 |
| 12 | 14874679296 |
| 13 | 97955205120 |
| 14 | 642150789120 |
| 15 | 4192482779136 |
| 16 | 27270729105408 |
| 17 | 176789554200576 |
| 18 | 1142549512519680 |
| 19 | 7363096858460160 |
| 20 | 47326939807481856 |
| 21 | 303461150525227008 |
| 22 | 1941420131673440256 |