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 | 81 |
| 3 | 177 |
| 4 | 530 |
| 5 | 1322 |
| 6 | 2749 |
| 7 | 6217 |
| 8 | 12712 |
| 9 | 25908 |
| 10 | 52474 |
| 11 | 103704 |
| 12 | 205390 |
| 13 | 402848 |
| 14 | 787367 |
| 15 | 1536289 |
| 16 | 2987863 |
| 17 | 5806685 |
| 18 | 11270614 |
| 19 | 21859130 |
| 20 | 42378217 |
| 21 | 82121061 |
| 22 | 159101032 |
| 23 | 308184196 |
| 24 | 596883878 |
| 25 | 1155938528 |
| 26 | 2238468542 |
| 27 | 4334604962 |