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) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 39 |
| 3 | 261 |
| 4 | 1779 |
| 5 | 12288 |
| 6 | 85734 |
| 7 | 602871 |
| 8 | 4265859 |
| 9 | 30338604 |
| 10 | 216677490 |
| 11 | 1552999242 |
| 12 | 11164548078 |
| 13 | 80471658192 |
| 14 | 581340627372 |
| 15 | 4208086875915 |
| 16 | 30514467991011 |
| 17 | 221620953353844 |
| 18 | 1611867544369146 |
| 19 | 11738194502675910 |
| 20 | 85580528620970874 |
| 21 | 624605115244327776 |
| 22 | 4563036506245946964 |