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 | 7 |
| 3 | -71 |
| 4 | 1001 |
| 5 | -18089 |
| 6 | 398959 |
| 7 | -10391023 |
| 8 | 312129649 |
| 9 | -10622799089 |
| 10 | 403978495031 |
| 11 | -16977719590391 |
| 12 | 781379079653017 |
| 13 | -39085931702241241 |
| 14 | 2111421691000680031 |
| 15 | -122501544009741683039 |
| 16 | 7597207150294985028449 |
| 17 | -501538173463478753560673 |