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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 32 |
| 6 | 99 |
| 7 | 318 |
| 8 | 1051 |
| 9 | 3550 |
| 10 | 12200 |
| 11 | 42520 |
| 12 | 149930 |
| 13 | 533890 |
| 14 | 1917181 |
| 15 | 6934722 |
| 16 | 25243539 |
| 17 | 92405718 |
| 18 | 339940116 |
| 19 | 1256122632 |
| 20 | 4660081434 |
| 21 | 17350844808 |
| 22 | 64814186646 |
| 23 | 242838410652 |
| 24 | 912333763806 |
| 25 | 3436240272972 |
| 26 | 12972454874704 |
| 27 | 49078874293528 |
| 28 | 186051766180496 |