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 | 8 |
| 3 | 24 |
| 4 | 112 |
| 5 | 736 |
| 6 | 3776 |
| 7 | 40192 |
| 8 | 391424 |
| 9 | 4203008 |
| 10 | 85312512 |
| 11 | 1270368256 |
| 12 | 32235102208 |
| 13 | 1038278549504 |
| 14 | 27640704385024 |
| 15 | 1549962593927168 |
| 16 | 73624753456480256 |
| 17 | 4273828146025070592 |
| 18 | 435765959975516766208 |