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 | 2 |
| 4 | 3 |
| 5 | 40 |
| 6 | 5 |
| 7 | 12 |
| 8 | 25 |
| 9 | 1122 |
| 10 | 13 |
| 11 | 420 |
| 12 | 1103 |
| 13 | 12324 |
| 14 | 421 |
| 15 | 4960 |
| 16 | 11289 |
| 17 | 232582 |
| 18 | 4961 |
| 19 | 16356 |
| 20 | 107073 |