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 | 2 |
| 2 | 3 |
| 3 | 4 |
| 4 | 16 |
| 5 | 12 |
| 6 | 60 |
| 7 | 96 |
| 8 | 294 |
| 9 | 720 |
| 10 | 1936 |
| 11 | 3920 |
| 12 | 9680 |
| 13 | 33712 |
| 14 | 83248 |
| 15 | 303408 |
| 16 | 1517040 |
| 17 | 5207472 |
| 18 | 26972352 |
| 19 | 74469808 |
| 20 | 255166128 |