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 | 2 |
| 4 | 2 |
| 5 | 4 |
| 6 | 10 |
| 7 | 20 |
| 8 | 38 |
| 9 | 82 |
| 10 | 164 |
| 11 | 328 |
| 12 | 660 |
| 13 | 1320 |
| 14 | 2640 |
| 15 | 5304 |
| 16 | 10596 |
| 17 | 21192 |
| 18 | 42424 |
| 19 | 84848 |
| 20 | 169668 |
| 21 | 339428 |
| 22 | 678856 |
| 23 | 1357712 |
| 24 | 2715548 |
| 25 | 5431096 |
| 26 | 10862192 |
| 27 | 21724746 |
| 28 | 43449380 |
| 29 | 86898760 |
| 30 | 173798220 |
| 31 | 347596440 |
| 32 | 695192670 |