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 | 4 |
| 2 | 7 |
| 3 | 15 |
| 4 | 31 |
| 5 | 65 |
| 6 | 136 |
| 7 | 285 |
| 8 | 597 |
| 9 | 1251 |
| 10 | 2621 |
| 11 | 5492 |
| 12 | 11507 |
| 13 | 24111 |
| 14 | 50519 |
| 15 | 105853 |