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) |
|---|---|
| 1 | 0 |
| 2 | 4 |
| 3 | 16 |
| 4 | 52 |
| 5 | 160 |
| 6 | 9232 |
| 7 | 13120 |
| 8 | 39364 |
| 9 | 41524 |
| 10 | 250504 |
| 11 | 1276936 |
| 12 | 6810136 |
| 13 | 8153620 |
| 14 | 27114424 |
| 15 | 50143264 |
| 16 | 106358020 |
| 17 | 121012864 |
| 18 | 593279152 |
| 19 | 1570824736 |
| 20 | 2482111348 |
| 21 | 2798323360 |
| 22 | 17202377752 |