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 | 30 |
| 3 | 12 |
| 4 | 1 |
| 5 | 2700 |
| 6 | 1920 |
| 7 | 426 |
| 8 | 36 |
| 9 | 1 |
| 10 | 491400 |
| 11 | 478800 |
| 12 | 162540 |
| 13 | 25344 |
| 14 | 1956 |
| 15 | 72 |
| 16 | 1 |
| 17 | 150368400 |
| 18 | 181440000 |
| 19 | 80451000 |
| 20 | 17624880 |
| 21 | 2130660 |
| 22 | 147840 |
| 23 | 5820 |
| 24 | 120 |
| 25 | 1 |
| 26 | 69470200800 |
| 27 | 98424849600 |
| 28 | 52905560400 |
| 29 | 14618016000 |
| 30 | 2346624000 |
| 31 | 232202880 |