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 | 19 |
| 6 | 330 |
| 7 | 4498 |
| 8 | 51756 |
| 9 | 548746 |
| 10 | 5517814 |
| 11 | 54024702 |
| 12 | 520188423 |
| 13 | 4957098874 |
| 14 | 46933220241 |
| 15 | 442604975423 |
| 16 | 4164551600019 |
| 17 | 39140839016528 |
| 18 | 367734226199966 |