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 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | -3 |
| 6 | -50 |
| 7 | -237 |
| 8 | -872 |
| 9 | -2375 |
| 10 | -3522 |
| 11 | 11383 |
| 12 | 140170 |
| 13 | 830999 |
| 14 | 3797676 |
| 15 | 13901117 |
| 16 | 36231696 |
| 17 | 12991001 |
| 18 | -656219096 |
| 19 | -5809148691 |
| 20 | -35189341480 |
| 21 | -173155983991 |
| 22 | -699938697650 |
| 23 | -2079618264082 |
| 24 | -1460269315332 |
| 25 | 39890883936437 |
| 26 | 413233629798312 |
| 27 | 2857552649413347 |