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 | 0 |
| 1 | 7 |
| 2 | 20 |
| 3 | 46 |
| 4 | 98 |
| 5 | 202 |
| 6 | 410 |
| 7 | 826 |
| 8 | 1658 |
| 9 | 3322 |
| 10 | 6650 |
| 11 | 13306 |
| 12 | 26618 |
| 13 | 53242 |
| 14 | 106490 |
| 15 | 212986 |
| 16 | 425978 |
| 17 | 851962 |
| 18 | 1703930 |
| 19 | 3407866 |
| 20 | 6815738 |
| 21 | 13631482 |
| 22 | 27262970 |
| 23 | 54525946 |
| 24 | 109051898 |
| 25 | 218103802 |
| 26 | 436207610 |
| 27 | 872415226 |
| 28 | 1744830458 |
| 29 | 3489660922 |