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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 12 |
| 6 | 30 |
| 7 | 69 |
| 8 | 150 |
| 9 | 317 |
| 10 | 659 |
| 11 | 1361 |
| 12 | 2784 |
| 13 | 5686 |
| 14 | 11557 |
| 15 | 23445 |
| 16 | 47472 |
| 17 | 95991 |
| 18 | 193891 |
| 19 | 391266 |
| 20 | 788979 |
| 21 | 1589856 |
| 22 | 3201863 |
| 23 | 6445059 |
| 24 | 12967425 |
| 25 | 26080302 |
| 26 | 52434693 |
| 27 | 105386552 |
| 28 | 211751544 |
| 29 | 425359720 |
| 30 | 854245385 |
| 31 | 1715204991 |