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 | 0 |
| 10 | 1 |
| 11 | 2 |
| 12 | 4 |
| 13 | 7 |
| 14 | 14 |
| 15 | 28 |
| 16 | 56 |
| 17 | 112 |
| 18 | 224 |
| 19 | 448 |
| 20 | 896 |
| 21 | 1791 |
| 22 | 3580 |
| 23 | 7156 |
| 24 | 14305 |
| 25 | 28596 |
| 26 | 57164 |
| 27 | 114272 |
| 28 | 228432 |
| 29 | 456640 |
| 30 | 912832 |
| 31 | 1824768 |
| 32 | 3647745 |
| 33 | 7291910 |
| 34 | 14576664 |
| 35 | 29139023 |
| 36 | 58249450 |
| 37 | 116441736 |
| 38 | 232769200 |
| 39 | 465309968 |
| 40 | 930163296 |
| 41 | 1859413760 |