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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 2 |
| 5 | 2 |
| 6 | 4 |
| 7 | 8 |
| 8 | 18 |
| 9 | 34 |
| 10 | 68 |
| 11 | 136 |
| 12 | 274 |
| 13 | 546 |
| 14 | 1092 |
| 15 | 2184 |
| 16 | 4370 |
| 17 | 8738 |
| 18 | 17476 |
| 19 | 34952 |
| 20 | 69906 |
| 21 | 139810 |
| 22 | 279620 |
| 23 | 559240 |
| 24 | 1118482 |
| 25 | 2236962 |
| 26 | 4473924 |
| 27 | 8947848 |
| 28 | 17895698 |
| 29 | 35791394 |
| 30 | 71582788 |
| 31 | 143165576 |
| 32 | 286331154 |
| 33 | 572662306 |
| 34 | 1145324612 |
| 35 | 2290649224 |