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 | 0 |
| 1 | 2 |
| 2 | 8 |
| 3 | 38 |
| 4 | 192 |
| 5 | 1002 |
| 6 | 5336 |
| 7 | 28814 |
| 8 | 157184 |
| 9 | 864146 |
| 10 | 4780008 |
| 11 | 26572086 |
| 12 | 148321344 |
| 13 | 830764794 |
| 14 | 4666890936 |
| 15 | 26283115038 |
| 16 | 148348809216 |
| 17 | 838944980514 |
| 18 | 4752575891144 |
| 19 | 26964373486406 |
| 20 | 153196621856192 |
| 21 | 871460014012682 |
| 22 | 4962895187697048 |
| 23 | 28292329581548718 |