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 | 6 |
| 2 | -1 |
| 3 | 42 |
| 4 | -14 |
| 5 | 1 |
| 6 | 336 |
| 7 | -168 |
| 8 | 24 |
| 9 | -1 |
| 10 | 3024 |
| 11 | -2016 |
| 12 | 432 |
| 13 | -36 |
| 14 | 1 |
| 15 | 30240 |
| 16 | -25200 |
| 17 | 7200 |
| 18 | -900 |
| 19 | 50 |
| 20 | -1 |
| 21 | 332640 |
| 22 | -332640 |
| 23 | 118800 |
| 24 | -19800 |
| 25 | 1650 |
| 26 | -66 |
| 27 | 1 |
| 28 | 3991680 |
| 29 | -4656960 |
| 30 | 1995840 |
| 31 | -415800 |
| 32 | 46200 |
| 33 | -2772 |
| 34 | 84 |
| 35 | -1 |
| 36 | 51891840 |
| 37 | -69189120 |