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 | 7 |
| 4 | 45 |
| 5 | 115 |
| 6 | 681 |
| 7 | 1248 |
| 8 | 2481 |
| 9 | 2689 |
| 10 | 6198 |
| 11 | 13197 |
| 12 | 60126 |
| 13 | 100072 |