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 | -9 |
| 3 | -19 |
| 4 | -9 |
| 5 | 163 |
| 6 | 573 |
| 7 | 1127 |
| 8 | 109 |
| 9 | -7198 |
| 10 | -27159 |
| 11 | -58611 |
| 12 | -50378 |
| 13 | 157532 |
| 14 | 892986 |
| 15 | 2431694 |
| 16 | 4040909 |
| 17 | 1605559 |
| 18 | -16109148 |
| 19 | -68261139 |
| 20 | -167737209 |
| 21 | -263590908 |
| 22 | -109589779 |
| 23 | 934422499 |
| 24 | 3976197701 |
| 25 | 9922490735 |
| 26 | 16765911071 |
| 27 | 13022553978 |
| 28 | -33008232762 |