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 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 1 |
| 10 | 2 |
| 11 | 4 |
| 12 | 7 |
| 13 | 14 |
| 14 | 28 |
| 15 | 56 |
| 16 | 112 |
| 17 | 224 |
| 18 | 448 |
| 19 | 895 |
| 20 | 1788 |
| 21 | 3572 |
| 22 | 7137 |
| 23 | 14260 |
| 24 | 28492 |
| 25 | 56928 |
| 26 | 113744 |
| 27 | 227264 |
| 28 | 454080 |
| 29 | 907265 |
| 30 | 1812742 |
| 31 | 3621912 |
| 32 | 7236687 |
| 33 | 14459114 |
| 34 | 28889736 |
| 35 | 57722544 |
| 36 | 115331344 |
| 37 | 230435424 |
| 38 | 460416768 |
| 39 | 919926271 |
| 40 | 1838039800 |