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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 3 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 9 |
| 11 | 18 |
| 12 | -21 |
| 13 | 0 |
| 14 | 72 |
| 15 | 120 |
| 16 | -45 |
| 17 | -342 |
| 18 | 825 |
| 19 | 1296 |
| 20 | -630 |
| 21 | -2832 |
| 22 | 3411 |
| 23 | 21258 |
| 24 | -6624 |
| 25 | -40446 |
| 26 | 31338 |
| 27 | 209676 |
| 28 | 97677 |
| 29 | -665712 |
| 30 | 152427 |
| 31 | 2666574 |
| 32 | 1655280 |
| 33 | -6736512 |
| 34 | -5070123 |
| 35 | 35432550 |
| 36 | 32647365 |
| 37 | -83688480 |
| 38 | -96328908 |