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 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 11 |
| 5 | 34 |
| 6 | 82 |
| 7 | 287 |
| 8 | 923 |
| 9 | 3016 |
| 10 | 8664 |
| 11 | 37407 |
| 12 | 102983 |
| 13 | 414050 |
| 14 | 1488140 |
| 15 | 5330976 |
| 16 | 19367263 |
| 17 | 76887675 |
| 18 | 255935344 |
| 19 | 808348061 |
| 20 | 3420607749 |
| 21 | 14063447808 |
| 22 | 52376853939 |
| 23 | 178612888734 |
| 24 | 666146253450 |
| 25 | 2182739853536 |
| 26 | 10254827577242 |
| 27 | 31021294603020 |
| 28 | 132781022354213 |