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) |
|---|---|
| 17 | 1 |
| 18 | 3 |
| 19 | 14 |
| 20 | 40 |
| 21 | 156 |
| 22 | 554 |
| 23 | 2369 |
| 24 | 11841 |
| 25 | 60654 |
| 26 | 498320 |
| 27 | 2987689 |
| 28 | 15177178 |
| 29 | 96041346 |
| 30 | 656938806 |
| 31 | 4640699138 |
| 32 | 31263742313 |
| 33 | 221075005249 |