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 | 9 |
| 4 | -17 |
| 5 | -79 |
| 6 | -73 |
| 7 | 249 |
| 8 | 863 |
| 9 | 481 |
| 10 | -3353 |
| 11 | -9111 |
| 12 | -1457 |
| 13 | 42641 |
| 14 | 92567 |
| 15 | -28071 |
| 16 | -518977 |
| 17 | -897599 |
| 18 | 799687 |
| 19 | 6087369 |
| 20 | 8176303 |
| 21 | -14084239 |
| 22 | -69049993 |
| 23 | -67678791 |
| 24 | 209892383 |
| 25 | 758178721 |
| 26 | 466895527 |
| 27 | -2857102551 |
| 28 | -8048682737 |
| 29 | -1811852719 |