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 | 2 |
| 2 | 14 |
| 3 | 90 |
| 4 | 612 |
| 5 | 4608 |
| 6 | 38760 |
| 7 | 361440 |
| 8 | 3688560 |
| 9 | 41277600 |
| 10 | 501379200 |
| 11 | 6576837120 |
| 12 | 92697696000 |
| 13 | 1397414592000 |
| 14 | 22498705152000 |
| 15 | 382873642905600 |
| 16 | 6908854669516800 |
| 17 | 131496596027596800 |
| 18 | 2633684945988096000 |