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 | 2 |
| 2 | 3 |
| 3 | 14 |
| 4 | 20 |
| 5 | 110 |
| 6 | 154 |
| 7 | 910 |
| 8 | 1260 |
| 9 | 7752 |
| 10 | 10659 |
| 11 | 67298 |
| 12 | 92092 |
| 13 | 592020 |
| 14 | 807300 |
| 15 | 5259150 |
| 16 | 7152444 |
| 17 | 47071640 |
| 18 | 63882940 |
| 19 | 423830264 |
| 20 | 574221648 |
| 21 | 3834669566 |
| 22 | 5188082354 |
| 23 | 34834267234 |
| 24 | 47073334100 |
| 25 | 317506779800 |
| 26 | 428634152730 |
| 27 | 2902365981900 |
| 28 | 3914819231400 |