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 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 1 |
| 6 | 38 |
| 7 | 57 |
| 8 | 27 |
| 9 | 7 |
| 10 | 13872 |
| 11 | 18544 |
| 12 | 9280 |
| 13 | 2080 |
| 14 | 192 |
| 15 | 83360520 |
| 16 | 104208775 |
| 17 | 52110500 |
| 18 | 13035000 |
| 19 | 1632750 |
| 20 | 82355 |