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 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 30 |
| 6 | 120 |
| 7 | 210 |
| 8 | 840 |
| 9 | 2310 |
| 10 | 7560 |
| 11 | 9240 |
| 12 | 30030 |
| 13 | 83160 |
| 14 | 120120 |
| 15 | 480480 |
| 16 | 1081080 |
| 17 | 1921920 |
| 18 | 2042040 |
| 19 | 8168160 |
| 20 | 18378360 |
| 21 | 32672640 |
| 22 | 38798760 |
| 23 | 155195040 |
| 24 | 349188840 |
| 25 | 620780160 |
| 26 | 892371480 |
| 27 | 3569485920 |
| 28 | 8031343320 |
| 29 | 14277943680 |
| 30 | 25878772920 |
| 31 | 103515091680 |