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 | 4 |
| 2 | 8 |
| 3 | 20 |
| 4 | 60 |
| 5 | 188 |
| 6 | 632 |
| 7 | 2192 |
| 8 | 7712 |
| 9 | 27596 |
| 10 | 99880 |
| 11 | 364724 |
| 12 | 1342184 |
| 13 | 4971068 |
| 14 | 18512792 |
| 15 | 69273668 |
| 16 | 260301176 |
| 17 | 981706832 |
| 18 | 3714566312 |
| 19 | 14096303344 |
| 20 | 53634713552 |
| 21 | 204560302844 |
| 22 | 781874936816 |
| 23 | 2994414645860 |
| 24 | 11488774559636 |