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 | 1 |
| 2 | 6 |
| 3 | 68 |
| 4 | 1206 |
| 5 | 29982 |
| 6 | 981476 |
| 7 | 40515568 |
| 8 | 2044492988 |
| 9 | 123175320988 |
| 10 | 8697475219688 |
| 11 | 709097832452880 |
| 12 | 65934837808883016 |
| 13 | 6920436929999656936 |
| 14 | 812724019581549433520 |
| 15 | 105986960037601701495680 |