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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 60 |
| 6 | 60 |
| 7 | 420 |
| 8 | 1680 |
| 9 | 5040 |
| 10 | 5040 |
| 11 | 55440 |
| 12 | 332640 |
| 13 | 4324320 |
| 14 | 8648640 |
| 15 | 43243200 |
| 16 | 172972800 |
| 17 | 2940537600 |
| 18 | 8821612800 |
| 19 | 167610643200 |
| 20 | 335221286400 |
| 21 | 7039647014400 |
| 22 | 14079294028800 |
| 23 | 323823762662400 |
| 24 | 647647525324800 |
| 25 | 3238237626624000 |
| 26 | 6476475253248000 |