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 | 3 |
| 3 | 4 |
| 4 | 15 |
| 5 | 40 |
| 6 | 146 |
| 7 | 514 |
| 8 | 2032 |
| 9 | 8076 |
| 10 | 33310 |
| 11 | 138966 |
| 12 | 589618 |
| 13 | 2525494 |
| 14 | 10923868 |
| 15 | 47599638 |
| 16 | 208824200 |
| 17 | 921391230 |
| 18 | 4086463748 |
| 19 | 18206487792 |