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 | 2 |
| 2 | 6 |
| 3 | 2 |
| 4 | 40 |
| 5 | 32 |
| 6 | 464 |
| 7 | 272 |
| 8 | 7040 |
| 9 | 4864 |
| 10 | 136448 |
| 11 | 87808 |
| 12 | 3177472 |
| 13 | 2123776 |
| 14 | 86861824 |
| 15 | 57128960 |
| 16 | 2720112640 |
| 17 | 1806049280 |
| 18 | 96095928320 |
| 19 | 63587041280 |
| 20 | 3778819358720 |
| 21 | 2507078533120 |
| 22 | 163724570132480 |
| 23 | 108568842403840 |
| 24 | 7748467910901760 |