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 | 68 |
| 4 | 312 |
| 5 | 1560 |
| 6 | 8528 |
| 7 | 50864 |
| 8 | 329248 |
| 9 | 2298592 |
| 10 | 17203264 |
| 11 | 137289920 |