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 | -3 |
| 3 | -26 |
| 4 | -15 |
| 5 | -3124 |
| 6 | 45864 |
| 7 | -823542 |
| 8 | -255 |
| 9 | -19682 |
| 10 | 9990233352 |
| 11 | -285311670610 |
| 12 | 2176246800 |
| 13 | -302875106592252 |
| 14 | 11111328602468784 |
| 15 | 437893859848932344 |
| 16 | -65535 |
| 17 | -827240261886336764176 |
| 18 | 101559568985784 |
| 19 | -1978419655660313589123978 |
| 20 | 99999904632567310800 |