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 | 22 |
| 3 | 62 |
| 4 | 484 |
| 5 | 2226 |
| 6 | 13056 |
| 7 | 67936 |
| 8 | 374342 |
| 9 | 2006006 |
| 10 | 10894988 |
| 11 | 58789204 |
| 12 | 318224626 |
| 13 | 1719926984 |
| 14 | 9302621856 |
| 15 | 50297494954 |
| 16 | 271995651900 |
| 17 | 1470758893578 |
| 18 | 7953136851900 |
| 19 | 43005796059376 |
| 20 | 232551746953140 |
| 21 | 1257506529312924 |