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 | -5 |
| 2 | -15 |
| 3 | 355 |
| 4 | 4665 |
| 5 | -88805 |
| 6 | -2984415 |
| 7 | 37043155 |
| 8 | 3157381065 |
| 9 | -10240455605 |
| 10 | -4883191732815 |
| 11 | -46188388946045 |
| 12 | 10124441425941465 |
| 13 | 280075126224969595 |
| 14 | -26112838782751585215 |
| 15 | -1459429976295088887245 |