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 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 5 |
| 7 | 39 |
| 8 | 394 |
| 9 | 2784 |
| 10 | 19164 |
| 11 | 118762 |
| 12 | 579460 |
| 13 | 3110267 |
| 14 | 15264387 |
| 15 | 75007623 |
| 16 | 369928203 |
| 17 | 1817475619 |
| 18 | 8913862144 |
| 19 | 43914857957 |
| 20 | 216555328193 |
| 21 | 1070588132492 |