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 | 3 |
| 4 | 7 |
| 5 | 15 |
| 6 | 37 |
| 7 | 71 |
| 8 | 159 |
| 9 | 303 |
| 10 | 681 |
| 11 | 1291 |
| 12 | 2887 |
| 13 | 5471 |
| 14 | 12237 |
| 15 | 23183 |
| 16 | 51839 |
| 17 | 98207 |
| 18 | 219601 |
| 19 | 416019 |
| 20 | 930247 |
| 21 | 1762287 |
| 22 | 3940597 |
| 23 | 7465175 |
| 24 | 16692639 |
| 25 | 31622991 |