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 | 6 |
| 2 | -15 |
| 3 | -386 |
| 4 | -1695 |
| 5 | 1182 |
| 6 | 70993 |
| 7 | 705894 |
| 8 | 5502657 |
| 9 | 39822166 |
| 10 | 281475249 |
| 11 | 1975555182 |
| 12 | 13838301217 |
| 13 | 96884183598 |
| 14 | 678215543313 |
| 15 | 4747550119318 |
| 16 | 33232913792385 |
| 17 | 232630489849638 |
| 18 | 1628413563898225 |
| 19 | 11398895138327262 |