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 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 9 |
| 5 | 21 |
| 6 | 49 |
| 7 | 105 |
| 8 | 225 |
| 9 | 465 |
| 10 | 961 |
| 11 | 1953 |
| 12 | 3969 |
| 13 | 8001 |
| 14 | 16129 |
| 15 | 32385 |
| 16 | 65025 |
| 17 | 130305 |
| 18 | 261121 |
| 19 | 522753 |
| 20 | 1046529 |
| 21 | 2094081 |
| 22 | 4190209 |
| 23 | 8382465 |
| 24 | 16769025 |
| 25 | 33542145 |
| 26 | 67092481 |
| 27 | 134193153 |
| 28 | 268402689 |
| 29 | 536821761 |
| 30 | 1073676289 |
| 31 | 2147385345 |