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 | 3 |
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 1 |
| 5 | 43 |
| 6 | 79 |
| 7 | 717 |
| 8 | 3481 |
| 9 | 100189 |
| 10 | 533077 |
| 11 | 1777722593 |
| 12 | 156155179 |
| 13 | 74216302403 |
| 14 | 15537618841 |
| 15 | 11069240202341 |
| 16 | 5762870563187 |
| 17 | 2682308717818019 |
| 18 | 927089189292457 |
| 19 | 3726882116303677517 |
| 20 | 35762248102620751 |
| 21 | 1529769611935770520751 |
| 22 | 1576432862602739502061 |