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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 720 |
| 7 | 5040 |
| 8 | 40320 |
| 9 | 362880 |
| 10 | 3628800 |
| 11 | 39916800 |
| 12 | 479001600 |
| 13 | 1932053504 |
| 14 | 1278945280 |
| 15 | 2004310016 |
| 16 | 2004189184 |
| 17 | -288522240 |
| 18 | -898433024 |
| 19 | 109641728 |
| 20 | -2102132736 |
| 21 | -1195114496 |
| 22 | -522715136 |
| 23 | 862453760 |
| 24 | -775946240 |
| 25 | 2076180480 |
| 26 | -1853882368 |
| 27 | 1484783616 |
| 28 | -1375731712 |
| 29 | -1241513984 |
| 30 | 1409286144 |
| 31 | 738197504 |
| 32 | -2147483648 |
| 33 | -2147483648 |
| 34 | 0 |
| 35 | 0 |
| 36 | 0 |