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 | 4 |
| 2 | 16 |
| 3 | 76 |
| 4 | 384 |
| 5 | 2004 |
| 6 | 10672 |
| 7 | 57628 |
| 8 | 314368 |
| 9 | 1728292 |
| 10 | 9560016 |
| 11 | 53144172 |
| 12 | 296642688 |
| 13 | 1661529588 |
| 14 | 9333781872 |
| 15 | 52566230076 |
| 16 | 296697618432 |
| 17 | 1677889961028 |
| 18 | 9505151782288 |
| 19 | 53928746972812 |
| 20 | 306393243712384 |
| 21 | 1742920028025364 |
| 22 | 9925790375394096 |
| 23 | 56584659163097436 |