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 | -3 |
| 3 | -31 |
| 4 | 453 |
| 5 | 15641 |
| 6 | -973443 |
| 7 | -126707471 |
| 8 | 32192101173 |
| 9 | 16547934365321 |
| 10 | -16912274385623763 |
| 11 | -34670312866958030751 |
| 12 | 141940412456349939507813 |
| 13 | 1163060052394732038435530361 |
| 14 | -19053251054424307861590927924003 |
| 15 | -624375047526738670923288994646642991 |