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 | 168 |
| 3 | 58800 |
| 4 | 20176632 |
| 5 | 6920642400 |
| 6 | 2373780746568 |
| 7 | 814206798896400 |
| 8 | 279272932041230232 |
| 9 | 95790615690280324800 |
| 10 | 32856181181767119892968 |
| 11 | 11269670145346128902694000 |
| 12 | 3865496859853722261079883832 |
| 13 | 1325865422929826735882591047200 |
| 14 | 454771840064930570410054065439368 |