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) |
|---|---|
| 1 | 11 |
| 2 | 56 |
| 3 | 228 |
| 4 | 884 |
| 5 | 3436 |
| 6 | 13440 |
| 7 | 52700 |
| 8 | 206708 |
| 9 | 810664 |
| 10 | 3178940 |
| 11 | 12465596 |
| 12 | 48881440 |
| 13 | 191679756 |
| 14 | 751638532 |
| 15 | 2947419144 |
| 16 | 11557788332 |
| 17 | 45321842028 |
| 18 | 177721660896 |
| 19 | 696904347580 |
| 20 | 2732788270804 |
| 21 | 10716150306024 |
| 22 | 42021505514844 |