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 | 3 |
| 2 | -2 |
| 3 | 9 |
| 4 | -16 |
| 5 | 4 |
| 6 | 27 |
| 7 | -98 |
| 8 | 60 |
| 9 | 0 |
| 10 | 81 |
| 11 | -544 |
| 12 | 616 |
| 13 | 0 |
| 14 | -96 |
| 15 | 243 |
| 16 | -2882 |
| 17 | 5400 |
| 18 | 0 |
| 19 | -3360 |
| 20 | 960 |
| 21 | 729 |
| 22 | -14896 |
| 23 | 43564 |
| 24 | 0 |
| 25 | -72480 |
| 26 | 46080 |
| 27 | -5760 |
| 28 | 2187 |
| 29 | -75938 |
| 30 | 334740 |
| 31 | 0 |
| 32 | -1246560 |
| 33 | 1323840 |
| 34 | -362880 |
| 35 | 0 |
| 36 | 6561 |
| 37 | -384064 |
| 38 | 2495056 |
| 39 | 0 |
| 40 | -18801216 |
| 41 | 29675520 |