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 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 9 |
| 5 | 20 |
| 6 | 42 |
| 7 | 85 |
| 8 | 171 |
| 9 | 343 |
| 10 | 687 |
| 11 | 1375 |
| 12 | 2751 |
| 13 | 5504 |
| 14 | 11009 |
| 15 | 22019 |
| 16 | 44039 |
| 17 | 88080 |
| 18 | 176162 |
| 19 | 352325 |
| 20 | 704651 |
| 21 | 1409303 |
| 22 | 2818607 |
| 23 | 5637215 |
| 24 | 11274431 |
| 25 | 22548863 |
| 26 | 45097727 |
| 27 | 90195455 |
| 28 | 180390911 |
| 29 | 360781823 |
| 30 | 721563647 |
| 31 | 1443127295 |
| 32 | 2886254591 |