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 | 0 |
| 2 | 1 |
| 3 | 15 |
| 4 | 101 |
| 5 | 773 |
| 6 | 5569 |
| 7 | 42352 |
| 8 | 334180 |
| 9 | 2695109 |
| 10 | 22160841 |
| 11 | 185402143 |
| 12 | 1573331564 |
| 13 | 13515180171 |
| 14 | 117333792953 |
| 15 | 1028087693781 |
| 16 | 9081524454631 |
| 17 | 80799078096971 |
| 18 | 723494891844589 |