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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 19 |
| 6 | 39 |
| 7 | 79 |
| 8 | 158 |
| 9 | 316 |
| 10 | 632 |
| 11 | 1265 |
| 12 | 2531 |
| 13 | 5062 |
| 14 | 10125 |
| 15 | 20251 |
| 16 | 40503 |
| 17 | 81006 |
| 18 | 162013 |
| 19 | 324027 |
| 20 | 648055 |
| 21 | 1296111 |
| 22 | 2592222 |
| 23 | 5184444 |
| 24 | 10368889 |
| 25 | 20737779 |
| 26 | 41475558 |
| 27 | 82951117 |
| 28 | 165902235 |
| 29 | 331804471 |
| 30 | 663608942 |
| 31 | 1327217884 |
| 32 | 2654435769 |
| 33 | 5308871538 |