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 | 3 |
| 2 | 3 |
| 3 | 2 |
| 4 | 9 |
| 5 | 18 |
| 6 | 20 |
| 7 | 24 |
| 8 | 36 |
| 9 | 24 |
| 10 | 108 |
| 11 | 468 |
| 12 | 1554 |
| 13 | 4308 |
| 14 | 10128 |
| 15 | 21144 |
| 16 | 40080 |
| 17 | 68496 |
| 18 | 105840 |
| 19 | 153120 |
| 20 | 206976 |
| 21 | 259648 |
| 22 | 317952 |