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) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 24 |
| 4 | 25 |
| 5 | 2 |
| 6 | -2 |
| 7 | 0 |
| 8 | -2 |
| 9 | 1 |
| 10 | -3 |
| 11 | 3 |
| 12 | -6 |
| 13 | 9 |
| 14 | -19 |
| 15 | 35 |
| 16 | -70 |
| 17 | 140 |
| 18 | -289 |
| 19 | 603 |
| 20 | -1283 |
| 21 | 2763 |
| 22 | -6031 |
| 23 | 13307 |
| 24 | -29660 |
| 25 | 66710 |
| 26 | -151297 |
| 27 | 345755 |
| 28 | -795695 |
| 29 | 1842994 |
| 30 | -4294316 |
| 31 | 10061643 |
| 32 | -23696379 |
| 33 | 56076739 |
| 34 | -133301692 |
| 35 | 318212959 |
| 36 | -762636889 |
| 37 | 1834568152 |
| 38 | -4428667929 |
| 39 | 10726314536 |
| 40 | -26060812015 |
| 41 | 63505805734 |