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) |
|---|---|
| 3 | 1 |
| 4 | 16 |
| 5 | 144 |
| 6 | 1016 |
| 7 | 6271 |
| 8 | 35584 |
| 9 | 190628 |
| 10 | 979496 |
| 11 | 4876530 |
| 12 | 23686560 |
| 13 | 112796176 |
| 14 | 528495600 |
| 15 | 2442949979 |
| 16 | 11163970432 |
| 17 | 50520351612 |
| 18 | 226688100104 |
| 19 | 1009648508590 |
| 20 | 4467591809376 |
| 21 | 19654294688768 |
| 22 | 86018255452048 |
| 23 | 374715017442966 |
| 24 | 1625489878136576 |
| 25 | 7024392489806344 |