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 | 4 |
| 2 | 34 |
| 3 | 308 |
| 4 | 3024 |
| 5 | 31680 |
| 6 | 349206 |
| 7 | 4008004 |
| 8 | 47530912 |
| 9 | 579058896 |
| 10 | 7215393640 |
| 11 | 91644262864 |
| 12 | 1183274479040 |
| 13 | 15497363512800 |
| 14 | 205519758825150 |
| 15 | 2755739674246500 |
| 16 | 37314861293793600 |
| 17 | 509727100259638800 |