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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 4 |
| 5 | 0 |
| 6 | 4 |
| 7 | 4 |
| 8 | 12288 |
| 9 | 81920 |
| 10 | 0 |
| 11 | 0 |
| 12 | 278380544 |
| 13 | 4 |
| 14 | 4931584 |
| 15 | 278380544 |
| 16 | 14768867966976 |
| 17 | 4 |
| 18 | 128412352512 |
| 19 | 14768867966976 |
| 20 | 375877192068366336 |
| 21 | 14768867966976 |
| 22 | 14768867966976 |
| 23 | 375877192068366336 |