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 | 5 |
| 3 | 10 |
| 4 | 22 |
| 5 | 44 |
| 6 | 98 |
| 7 | 196 |
| 8 | 436 |
| 9 | 872 |
| 10 | 1940 |
| 11 | 3880 |
| 12 | 8632 |
| 13 | 17264 |
| 14 | 38408 |
| 15 | 76816 |
| 16 | 170896 |
| 17 | 341792 |
| 18 | 760400 |
| 19 | 1520800 |
| 20 | 3383392 |
| 21 | 6766784 |
| 22 | 15054368 |
| 23 | 30108736 |
| 24 | 66984256 |
| 25 | 133968512 |
| 26 | 298045760 |
| 27 | 596091520 |
| 28 | 1326151552 |
| 29 | 2652303104 |