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 | 7 |
| 3 | 21 |
| 4 | 147 |
| 5 | 1393 |
| 6 | 2569 |
| 7 | 7525 |
| 8 | 13748 |
| 9 | 30171 |
| 10 | 43491 |
| 11 | 100639 |
| 12 | 123456 |
| 13 | 224175 |
| 14 | 296991 |
| 15 | 495367 |
| 16 | 658684 |
| 17 | 1013008 |
| 18 | 1438440 |
| 19 | 1954357 |
| 20 | 2310462 |
| 21 | 3813903 |
| 22 | 4092029 |
| 23 | 5916929 |
| 24 | 6974592 |
| 25 | 10276475 |
| 26 | 10989267 |
| 27 | 14919105 |
| 28 | 21957309 |
| 29 | 26812232 |
| 30 | 36865003 |