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 | 6 |
| 4 | 1 |
| 5 | 24 |
| 6 | 6 |
| 7 | 120 |
| 8 | 36 |
| 9 | 1 |
| 10 | 720 |
| 11 | 240 |
| 12 | 12 |
| 13 | 5040 |
| 14 | 1800 |
| 15 | 120 |
| 16 | 1 |
| 17 | 40320 |
| 18 | 15120 |
| 19 | 1200 |
| 20 | 20 |
| 21 | 362880 |
| 22 | 141120 |
| 23 | 12600 |
| 24 | 300 |
| 25 | 1 |
| 26 | 3628800 |
| 27 | 1451520 |
| 28 | 141120 |
| 29 | 4200 |
| 30 | 30 |
| 31 | 39916800 |
| 32 | 16329600 |
| 33 | 1693440 |
| 34 | 58800 |
| 35 | 630 |
| 36 | 1 |
| 37 | 479001600 |
| 38 | 199584000 |
| 39 | 21772800 |
| 40 | 846720 |
| 41 | 11760 |
| 42 | 42 |