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 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 20 |
| 7 | 47 |
| 8 | 113 |
| 9 | 281 |
| 10 | 706 |
| 11 | 1807 |
| 12 | 4671 |
| 13 | 12224 |
| 14 | 32247 |
| 15 | 85782 |
| 16 | 229683 |
| 17 | 618767 |
| 18 | 1675618 |
| 19 | 4559263 |
| 20 | 12457483 |
| 21 | 34168574 |
| 22 | 94040433 |
| 23 | 259637564 |
| 24 | 718892281 |
| 25 | 1995739380 |
| 26 | 5553867981 |
| 27 | 15490305017 |
| 28 | 43293762352 |
| 29 | 121235084565 |