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 | 5 |
| 5 | 14 |
| 6 | 47 |
| 7 | 172 |
| 8 | 691 |
| 9 | 2881 |
| 10 | 12449 |
| 11 | 54782 |
| 12 | 244992 |
| 13 | 1107240 |
| 14 | 5050360 |
| 15 | 23202236 |
| 16 | 107269382 |
| 17 | 498622480 |
| 18 | 2328953312 |
| 19 | 10924738869 |