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) |
|---|---|
| 3 | 0 |
| 4 | 24 |
| 5 | 444 |
| 6 | 4400 |
| 7 | 32120 |
| 8 | 195800 |
| 9 | 1062500 |
| 10 | 5326160 |
| 11 | 25243904 |
| 12 | 114876376 |
| 13 | 507259276 |
| 14 | 2189829808 |
| 15 | 9292526920 |
| 16 | 38917528600 |
| 17 | 161343812980 |
| 18 | 663661077072 |
| 19 | 2713224461136 |
| 20 | 11039636532120 |
| 21 | 44751359547420 |
| 22 | 180880752056880 |