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 | 1 |
| 1 | 6 |
| 2 | 14 |
| 3 | 22 |
| 4 | 46 |
| 5 | 86 |
| 6 | 174 |
| 7 | 342 |
| 8 | 686 |
| 9 | 1366 |
| 10 | 2734 |
| 11 | 5462 |
| 12 | 10926 |
| 13 | 21846 |
| 14 | 43694 |
| 15 | 87382 |
| 16 | 174766 |
| 17 | 349526 |
| 18 | 699054 |
| 19 | 1398102 |
| 20 | 2796206 |
| 21 | 5592406 |
| 22 | 11184814 |
| 23 | 22369622 |
| 24 | 44739246 |
| 25 | 89478486 |
| 26 | 178956974 |
| 27 | 357913942 |
| 28 | 715827886 |
| 29 | 1431655766 |
| 30 | 2863311534 |