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 | 2 |
| 2 | 1 |
| 3 | -3 |
| 4 | -7 |
| 5 | -17 |
| 6 | 2 |
| 7 | 101 |
| 8 | 247 |
| 9 | 571 |
| 10 | -1669 |
| 11 | -13766 |
| 12 | -43101 |
| 13 | -205897 |
| 14 | 1640929 |
| 15 | 8217293 |
| 16 | 101727662 |
| 17 | 173114917 |
| 18 | -5439590147 |
| 19 | -70987557871 |
| 20 | -993401657957 |
| 21 | 2105332714614 |
| 22 | 208894282701569 |
| 23 | 3110590234593151 |
| 24 | 37334338699443371 |
| 25 | -891470356091782993 |
| 26 | -33292234868859857114 |