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 | 1 |
| 2 | 3 |
| 3 | 15 |
| 4 | 120 |
| 5 | 360 |
| 6 | 360 |
| 7 | 4680 |
| 8 | 936 |
| 9 | 6552 |
| 10 | 19656 |
| 11 | 19656 |
| 12 | 12285 |
| 13 | 61425 |
| 14 | 61425 |
| 15 | 61425 |
| 16 | 982800 |
| 17 | 10810800 |
| 18 | 10810800 |
| 19 | 399999600 |
| 20 | 399999600 |
| 21 | 30769200 |
| 22 | 30769200 |
| 23 | 30769200 |
| 24 | 30769200 |
| 25 | 399999600 |
| 26 | 79999920 |
| 27 | 239999760 |
| 28 | 239999760 |
| 29 | 4559995440 |
| 30 | 911999088 |
| 31 | 55631944368 |
| 32 | 27815972184 |