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 | 2 |
| 4 | 4 |
| 5 | 14 |
| 6 | 46 |
| 7 | 224 |
| 8 | 1024 |
| 9 | 6320 |
| 10 | 36976 |
| 11 | 275792 |
| 12 | 1965664 |
| 13 | 17180144 |
| 14 | 144361456 |
| 15 | 1446351104 |
| 16 | 13997185024 |
| 17 | 158116017920 |
| 18 | 1731678144256 |
| 19 | 21771730437632 |
| 20 | 266182076161024 |
| 21 | 3686171162253824 |
| 22 | 49763143319190016 |
| 23 | 752594181757712384 |
| 24 | 11118629668610842624 |