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 | 1 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 1 |
| 11 | 2 |
| 12 | 4 |
| 13 | 8 |
| 14 | 16 |
| 15 | 32 |
| 16 | 63 |
| 17 | 126 |
| 18 | 252 |
| 19 | 504 |
| 20 | 1008 |
| 21 | 2015 |
| 22 | 4028 |
| 23 | 8052 |
| 24 | 16096 |
| 25 | 32176 |
| 26 | 64320 |
| 27 | 128577 |
| 28 | 257028 |
| 29 | 513804 |
| 30 | 1027104 |
| 31 | 2053200 |
| 32 | 4104385 |
| 33 | 8204742 |
| 34 | 16401432 |
| 35 | 32786768 |
| 36 | 65541360 |
| 37 | 131018400 |
| 38 | 261908223 |
| 39 | 523559418 |
| 40 | 1046605032 |
| 41 | 2092182960 |