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 | 0 |
| 3 | -1 |
| 4 | 0 |
| 5 | 3 |
| 6 | -1 |
| 7 | -12 |
| 8 | 9 |
| 9 | 55 |
| 10 | -67 |
| 11 | -267 |
| 12 | 468 |
| 13 | 1323 |
| 14 | -3180 |
| 15 | -6513 |
| 16 | 21267 |
| 17 | 30969 |
| 18 | -140581 |
| 19 | -135995 |
| 20 | 919698 |
| 21 | 494361 |
| 22 | -5954217 |
| 23 | -829116 |
| 24 | 38113425 |
| 25 | -9433359 |
| 26 | -240844482 |
| 27 | 154219912 |
| 28 | 1499076989 |
| 29 | -1585801575 |
| 30 | -9161079266 |
| 31 | 13958031252 |
| 32 | 54710928759 |
| 33 | -113373461193 |
| 34 | -317030478360 |
| 35 | 875491422246 |