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 | 2 |
| 1 | 8 |
| 2 | 40 |
| 3 | 224 |
| 4 | 1312 |
| 5 | 7808 |
| 6 | 46720 |
| 7 | 280064 |
| 8 | 1679872 |
| 9 | 10078208 |
| 10 | 60467200 |
| 11 | 362799104 |
| 12 | 2176786432 |
| 13 | 13060702208 |
| 14 | 78364180480 |
| 15 | 470185017344 |
| 16 | 2821109972992 |
| 17 | 16926659575808 |
| 18 | 101559956930560 |
| 19 | 609359740534784 |
| 20 | 3656158441111552 |