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 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | -2 |
| 6 | 1 |
| 7 | 5 |
| 8 | -20 |
| 9 | 16 |
| 10 | 1 |
| 11 | 7 |
| 12 | -70 |
| 13 | 336 |
| 14 | -272 |
| 15 | 1 |
| 16 | 9 |
| 17 | -168 |
| 18 | 2016 |
| 19 | -9792 |
| 20 | 7936 |
| 21 | 1 |
| 22 | 11 |
| 23 | -330 |
| 24 | 7392 |
| 25 | -89760 |
| 26 | 436480 |
| 27 | -353792 |
| 28 | 1 |
| 29 | 13 |
| 30 | -572 |
| 31 | 20592 |
| 32 | -466752 |
| 33 | 5674240 |
| 34 | -27595776 |
| 35 | 22368256 |
| 36 | 1 |
| 37 | 15 |
| 38 | -910 |
| 39 | 48048 |
| 40 | -1750320 |
| 41 | 39719680 |
| 42 | -482926080 |
| 43 | 2348666880 |
| 44 | -1903757312 |