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 | 3 |
| 1 | -1 |
| 2 | 5 |
| 3 | 3 |
| 4 | 13 |
| 5 | 19 |
| 6 | 45 |
| 7 | 83 |
| 8 | 173 |
| 9 | 339 |
| 10 | 685 |
| 11 | 1363 |
| 12 | 2733 |
| 13 | 5459 |
| 14 | 10925 |
| 15 | 21843 |
| 16 | 43693 |
| 17 | 87379 |
| 18 | 174765 |
| 19 | 349523 |
| 20 | 699053 |
| 21 | 1398099 |
| 22 | 2796205 |
| 23 | 5592403 |
| 24 | 11184813 |
| 25 | 22369619 |
| 26 | 44739245 |
| 27 | 89478483 |
| 28 | 178956973 |
| 29 | 357913939 |
| 30 | 715827885 |
| 31 | 1431655763 |
| 32 | 2863311533 |