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 | -3 |
| 2 | 5 |
| 3 | 1 |
| 4 | -7 |
| 5 | -75 |
| 6 | -99 |
| 7 | 1241 |
| 8 | 10161 |
| 9 | 18989 |
| 10 | -332299 |
| 11 | -3857551 |
| 12 | -14440151 |
| 13 | 141168997 |
| 14 | 2807256333 |
| 15 | 20182451657 |
| 16 | -42073176479 |
| 17 | -2999363709091 |
| 18 | -38439478980891 |
| 19 | -161835672017439 |
| 20 | 3439471815545177 |
| 21 | 87228227501354517 |
| 22 | 937579822282327421 |
| 23 | 216540362854403513 |
| 24 | -198501712690150659055 |