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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 360 |
| 11 | 720 |
| 12 | 7920 |
| 13 | 15120 |
| 14 | 103320 |
| 15 | 191520 |
| 16 | 1048320 |
| 17 | 1905120 |
| 18 | 9170280 |
| 19 | 16435440 |
| 20 | 72833040 |
| 21 | 129230640 |
| 22 | 541130040 |
| 23 | 953029440 |
| 24 | 3832187040 |
| 25 | 6711344640 |
| 26 | 26192766600 |
| 27 | 45674188560 |
| 28 | 174286672560 |
| 29 | 302899156560 |
| 30 | 1136023139160 |
| 31 | 1969147121760 |