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 | 4 |
| 4 | 12 |
| 5 | 24 |
| 6 | 48 |
| 7 | 240 |
| 8 | 480 |
| 9 | 1440 |
| 10 | 2880 |
| 11 | 5760 |
| 12 | 40320 |
| 13 | 120960 |
| 14 | 241920 |
| 15 | 483840 |
| 16 | 2419200 |
| 17 | 4838400 |
| 18 | 14515200 |
| 19 | 29030400 |
| 20 | 319334400 |
| 21 | 638668800 |
| 22 | 1916006400 |
| 23 | 3832012800 |
| 24 | 7664025600 |
| 25 | 38320128000 |
| 26 | 498161664000 |
| 27 | 996323328000 |
| 28 | 6974263296000 |
| 29 | 20922789888000 |
| 30 | 41845579776000 |
| 31 | 83691159552000 |