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 | -28 |
| 3 | -513 |
| 4 | -2800 |
| 5 | -7849 |
| 6 | 0 |
| 7 | 162287 |
| 8 | 1417472 |
| 9 | 9546255 |
| 10 | 59466176 |
| 11 | 361025495 |
| 12 | 2173796352 |
| 13 | 13055867207 |
| 14 | 78356634560 |
| 15 | 470173593951 |
| 16 | 2821093130240 |
| 17 | 16926635307167 |
| 18 | 101559922656192 |
| 19 | 609359692964615 |
| 20 | 3656158376062976 |
| 21 | 21936950554611735 |
| 22 | 131621703728887232 |
| 23 | 789730222905566927 |