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) |
|---|---|
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 17 |
| 7 | 62 |
| 8 | 275 |
| 9 | 1272 |
| 10 | 6225 |
| 11 | 31075 |
| 12 | 158376 |
| 13 | 816229 |
| 14 | 4251412 |
| 15 | 22319056 |
| 16 | 117998524 |
| 17 | 627573216 |
| 18 | 3355499036 |
| 19 | 18025442261 |
| 20 | 97239773408 |
| 21 | 526560862829 |
| 22 | 2861189112867 |
| 23 | 15595669996482 |
| 24 | 85252072993968 |
| 25 | 467247847612316 |
| 26 | 2567091151780343 |