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 | 3 |
| 2 | 31 |
| 3 | 520 |
| 4 | 11991 |
| 5 | 350889 |
| 6 | 12428746 |
| 7 | 516450792 |
| 8 | 24619176153 |
| 9 | 1323971052261 |
| 10 | 79280864647205 |
| 11 | 5231080689880500 |
| 12 | 377062508515478306 |
| 13 | 29479066783583059530 |
| 14 | 2484534527715953700780 |
| 15 | 224559818606249783480400 |
| 16 | 21666961097367611148157815 |
| 17 | 2222844864226101120054773295 |