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 | 4 |
| 3 | 10 |
| 4 | 38 |
| 5 | 142 |
| 6 | 470 |
| 7 | 1576 |
| 8 | 5940 |
| 9 | 22714 |
| 10 | 83456 |
| 11 | 305088 |
| 12 | 1158606 |
| 13 | 4456076 |
| 14 | 16946498 |
| 15 | 64189932 |
| 16 | 246350606 |
| 17 | 952607962 |
| 18 | 3675557676 |
| 19 | 14158562010 |
| 20 | 54805236890 |
| 21 | 213011072542 |
| 22 | 828185178452 |
| 23 | 3219077811678 |
| 24 | 12537974366478 |