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 | 2 |
| 4 | 6 |
| 5 | 18 |
| 6 | 65 |
| 7 | 241 |
| 8 | 984 |
| 9 | 4250 |
| 10 | 19590 |
| 11 | 95484 |
| 12 | 491459 |
| 13 | 2660030 |
| 14 | 15100494 |
| 15 | 89648378 |