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 | -71 |
| 3 | -215 |
| 4 | 15121 |
| 5 | 77041 |
| 6 | -5366519 |
| 7 | -38648231 |
| 8 | 2666077345 |
| 9 | 24927458401 |
| 10 | -1702690661159 |
| 11 | -19650460709879 |
| 12 | 1328880542928049 |
| 13 | 18306878596263505 |
| 14 | -1225525309584390359 |
| 15 | -19678858934618003399 |
| 16 | 1303888475416523584321 |
| 17 | 23973933968096463499969 |