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 | 0 |
| 3 | 85 |
| 4 | 156 |
| 5 | 2928 |
| 6 | 10880 |
| 7 | 101040 |
| 8 | 512500 |
| 9 | 3706880 |
| 10 | 21434424 |
| 11 | 142567200 |
| 12 | 873807820 |
| 13 | 5667708960 |
| 14 | 35731836120 |
| 15 | 230763023408 |
| 16 | 1477455187500 |
| 17 | 9565561745040 |
| 18 | 61835264112640 |
| 19 | 402074969960400 |
| 20 | 2616685548364056 |
| 21 | 17090016552803440 |
| 22 | 111789735908403600 |