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 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 5 |
| 6 | 7 |
| 7 | 7 |
| 8 | 881 |
| 9 | 3499 |
| 10 | 199 |
| 11 | 75307 |
| 12 | 110437 |
| 13 | 4943 |
| 14 | 31385539 |
| 15 | 115453391 |
| 16 | 53297929 |
| 17 | 3430751869 |
| 18 | 4808316343 |
| 19 | 8297644387 |
| 20 | 214861583621 |
| 21 | 5749146449311 |