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 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 1 |
| 9 | 0 |
| 10 | 1 |
| 11 | 2 |
| 12 | 4 |
| 13 | 8 |
| 14 | 16 |
| 15 | 32 |
| 16 | 64 |
| 17 | 128 |
| 18 | 256 |
| 19 | 511 |
| 20 | 1022 |
| 21 | 2043 |
| 22 | 4084 |
| 23 | 8164 |
| 24 | 16320 |
| 25 | 32624 |
| 26 | 65216 |
| 27 | 130368 |
| 28 | 260608 |
| 29 | 520960 |
| 30 | 1041409 |
| 31 | 2081796 |
| 32 | 4161549 |
| 33 | 8319014 |
| 34 | 16629864 |
| 35 | 33243408 |
| 36 | 66454192 |
| 37 | 132843168 |
| 38 | 265555968 |
| 39 | 530851328 |
| 40 | 1061181696 |
| 41 | 2121321983 |