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 | 4 |
| 2 | 10 |
| 3 | 16 |
| 4 | 9 |
| 5 | -40 |
| 6 | -169 |
| 7 | -376 |
| 8 | -490 |
| 9 | 36 |
| 10 | 2239 |
| 11 | 7120 |
| 12 | 13441 |
| 13 | 12844 |
| 14 | -16470 |
| 15 | -109144 |
| 16 | -283351 |
| 17 | -448120 |
| 18 | -229129 |
| 19 | 1196064 |
| 20 | 4879030 |
| 21 | 10675276 |
| 22 | 13561279 |
| 23 | -2161760 |
| 24 | -65753919 |
| 25 | -204313516 |
| 26 | -379184950 |
| 27 | -347399104 |
| 28 | 513198089 |