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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 16 |
| 6 | 36 |
| 7 | 144 |
| 8 | 576 |
| 9 | 900 |
| 10 | 3600 |
| 11 | 14400 |
| 12 | 32400 |
| 13 | 129600 |
| 14 | 435600 |
| 15 | 6969600 |
| 16 | 8643600 |
| 17 | 34574400 |
| 18 | 77792400 |
| 19 | 311169600 |
| 20 | 2498000400 |
| 21 | 2800526400 |
| 22 | 7779240000 |
| 23 | 9992001600 |
| 24 | 22482003600 |