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 | 2 |
| 2 | 5 |
| 3 | 11 |
| 4 | 11 |
| 5 | -77 |
| 6 | -704 |
| 7 | -3795 |
| 8 | -15686 |
| 9 | -48598 |
| 10 | -74009 |
| 11 | 376623 |
| 12 | 4438840 |
| 13 | 27458060 |
| 14 | 126898948 |
| 15 | 440550682 |
| 16 | 849522927 |
| 17 | -2621906045 |
| 18 | -39993434701 |
| 19 | -270428078305 |
| 20 | -1339005344985 |
| 21 | -5014789377825 |
| 22 | -11407684195950 |
| 23 | 18849058485855 |
| 24 | 417417757017612 |
| 25 | 3058172078113944 |