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 | 4 |
| 3 | 4 |
| 4 | 20 |
| 5 | 59 |
| 6 | 164 |
| 7 | 544 |
| 8 | 1730 |
| 9 | 5471 |
| 10 | 17765 |
| 11 | 55050 |
| 12 | 173906 |
| 13 | 546893 |