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 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 5 |
| 6 | 49 |
| 7 | 49 |
| 8 | 58 |
| 9 | 58 |
| 10 | 341 |
| 11 | 341 |
| 12 | 1963 |
| 13 | 1963 |
| 14 | 14479 |
| 15 | 14479 |
| 16 | 39236 |
| 17 | 39236 |
| 18 | -2286593 |
| 19 | -2286593 |
| 20 | 81626353 |
| 21 | 81626353 |
| 22 | -928516601 |
| 23 | -928516601 |
| 24 | 127463912438 |
| 25 | 127463912438 |
| 26 | -6013599342683 |
| 27 | -6013599342683 |
| 28 | 149990958958943 |