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 | 9 |
| 2 | 21 |
| 3 | 41 |
| 4 | 81 |
| 5 | 153 |
| 6 | 297 |
| 7 | 569 |
| 8 | 1113 |
| 9 | 2169 |
| 10 | 4281 |
| 11 | 8441 |
| 12 | 16761 |
| 13 | 33273 |
| 14 | 66297 |
| 15 | 132089 |
| 16 | 263673 |
| 17 | 526329 |
| 18 | 1051641 |
| 19 | 2101241 |
| 20 | 4200441 |
| 21 | 8396793 |
| 22 | 16789497 |
| 23 | 33570809 |
| 24 | 67133433 |
| 25 | 134250489 |
| 26 | 268484601 |
| 27 | 536936441 |
| 28 | 1073840121 |
| 29 | 2147614713 |
| 30 | 4295163897 |
| 31 | 8590196729 |
| 32 | 17180262393 |