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) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 17 |
| 4 | 37 |
| 5 | 79 |
| 6 | 163 |
| 7 | 331 |
| 8 | 673 |
| 9 | 1361 |
| 10 | 2729 |
| 11 | 5471 |
| 12 | 10949 |
| 13 | 21911 |
| 14 | 43853 |
| 15 | 87719 |
| 16 | 175447 |
| 17 | 350899 |
| 18 | 701819 |
| 19 | 1403641 |
| 20 | 2807303 |
| 21 | 5614657 |
| 22 | 11229331 |
| 23 | 22458671 |
| 24 | 44917381 |
| 25 | 89834777 |
| 26 | 179669557 |
| 27 | 359339171 |
| 28 | 718678369 |
| 29 | 1437356741 |
| 30 | 2874713497 |