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 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 0 |
| 12 | 0 |
| 13 | 0 |
| 14 | 0 |
| 15 | 0 |
| 16 | 0 |
| 17 | 0 |
| 18 | 0 |
| 19 | 0 |
| 20 | 0 |
| 21 | 0 |
| 22 | 1 |
| 23 | -22 |
| 24 | 253 |
| 25 | -2024 |
| 26 | 12650 |
| 27 | -65780 |
| 28 | 296010 |
| 29 | -1184040 |
| 30 | 4292145 |
| 31 | -14307150 |
| 32 | 44352165 |
| 33 | -129024480 |
| 34 | 354817320 |
| 35 | -927983760 |
| 36 | 2319959400 |
| 37 | -5567902560 |
| 38 | 12875774670 |
| 39 | -28781143380 |
| 40 | 62359143990 |