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 | 1 |
| 3 | 2 |
| 4 | 1 |
| 5 | 6 |
| 6 | 6 |
| 7 | 1 |
| 8 | 50 |
| 9 | 36 |
| 10 | 24 |
| 11 | 1 |
| 12 | 510 |
| 13 | 510 |
| 14 | 240 |
| 15 | 120 |
| 16 | 1 |
| 17 | 7682 |
| 18 | 7380 |
| 19 | 4800 |
| 20 | 1800 |
| 21 | 720 |
| 22 | 1 |
| 23 | 161406 |
| 24 | 141246 |
| 25 | 91560 |
| 26 | 47040 |
| 27 | 15120 |
| 28 | 5040 |
| 29 | 1 |
| 30 | 4747010 |
| 31 | 3444756 |
| 32 | 2162664 |
| 33 | 1134000 |
| 34 | 493920 |
| 35 | 141120 |
| 36 | 40320 |
| 37 | 1 |
| 38 | 194342910 |
| 39 | 110729310 |
| 40 | 61286400 |
| 41 | 32253480 |
| 42 | 14605920 |
| 43 | 5594400 |