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 | 0 |
| 5 | -4 |
| 6 | -14 |
| 7 | -34 |
| 8 | -64 |
| 9 | -80 |
| 10 | 16 |
| 11 | 496 |
| 12 | 1946 |
| 13 | 5266 |
| 14 | 10830 |
| 15 | 14886 |
| 16 | -884 |
| 17 | -92564 |
| 18 | -390404 |
| 19 | -1113380 |
| 20 | -2405649 |
| 21 | -3529749 |
| 22 | -360799 |
| 23 | 20509101 |
| 24 | 91770476 |
| 25 | 271807476 |
| 26 | 608858576 |
| 27 | 941203576 |
| 28 | 243522996 |
| 29 | -4977842140 |
| 30 | -23564569004 |
| 31 | -72054072364 |
| 32 | -166314098964 |