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 | 3 |
| 2 | 8 |
| 3 | 20 |
| 4 | 46 |
| 5 | 100 |
| 6 | 210 |
| 7 | 432 |
| 8 | 878 |
| 9 | 1772 |
| 10 | 3562 |
| 11 | 7144 |
| 12 | 14310 |
| 13 | 28644 |
| 14 | 57314 |
| 15 | 114656 |
| 16 | 229342 |
| 17 | 458716 |
| 18 | 917466 |
| 19 | 1834968 |
| 20 | 3669974 |
| 21 | 7339988 |
| 22 | 14680018 |
| 23 | 29360080 |
| 24 | 58720206 |
| 25 | 117440460 |
| 26 | 234880970 |
| 27 | 469761992 |
| 28 | 939524038 |
| 29 | 1879048132 |