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 | -1 |
| 9 | -1 |
| 10 | -7 |
| 11 | -8 |
| 12 | -35 |
| 13 | -44 |
| 14 | -154 |
| 15 | -208 |
| 16 | -637 |
| 17 | -910 |
| 18 | -2548 |
| 19 | -3808 |
| 20 | -9996 |
| 21 | -15504 |
| 22 | -38760 |
| 23 | -62015 |
| 24 | -149225 |
| 25 | -245135 |
| 26 | -572010 |
| 27 | -961125 |
| 28 | -2186886 |
| 29 | -3746886 |
| 30 | -8348172 |
| 31 | -14547183 |
| 32 | -31842580 |
| 33 | -56309764 |
| 34 | -121415344 |
| 35 | -217478888 |
| 36 | -462925232 |
| 37 | -838520240 |
| 38 | -1765205473 |
| 39 | -3228800413 |