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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 55 |
| 6 | 319 |
| 7 | 2233 |
| 8 | 17641 |
| 9 | 158769 |
| 10 | 1578667 |
| 11 | 17365337 |
| 12 | 207865289 |
| 13 | 2702248757 |
| 14 | 37786779669 |
| 15 | 566801695035 |
| 16 | 9063808803203 |
| 17 | 154084749654451 |