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) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 1 |
| 5 | 617 |
| 6 | 112 |
| 7 | 845 |
| 8 | 25376 |
| 9 | 2985 |
| 10 | 314 |
| 11 | 1597052 |
| 12 | 138874 |
| 13 | 1173486218 |
| 14 | 63368255819 |
| 15 | 4370224539 |
| 16 | 281949970 |
| 17 | 5377913733006 |
| 18 | 376453961310474 |
| 19 | 7345939461247630 |
| 20 | 572983277977315172 |
| 21 | 27950403803771471 |
| 22 | 1300018781570766 |