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 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 84 |
| 6 | 4686825 |
| 7 | 1 |
| 8 | 12870 |
| 9 | 3284214703056 |
| 10 | 10078751602022313874633200 |
| 11 | 1 |
| 12 | 3268760 |
| 13 | 9064807833193439800 |
| 14 | 25006639164538285144538957539300707000 |
| 15 | 137658555538877668586244095134027016988748997970545868021484500 |
| 16 | 1 |