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) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 44 |
| 4 | 149 |
| 5 | 479 |
| 6 | 1487 |
| 7 | 4503 |
| 8 | 13386 |
| 9 | 39226 |
| 10 | 113641 |
| 11 | 326173 |
| 12 | 928957 |
| 13 | 2628459 |
| 14 | 7395624 |
| 15 | 20708264 |
| 16 | 57739517 |
| 17 | 160391483 |
| 18 | 444068171 |
| 19 | 1225831551 |
| 20 | 3374848806 |
| 21 | 9268963318 |
| 22 | 25401364177 |
| 23 | 69472849849 |
| 24 | 189661024249 |
| 25 | 516904018899 |