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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 20 |
| 6 | 60 |
| 7 | 190 |
| 8 | 764 |
| 9 | 2337 |
| 10 | 9812 |
| 11 | 49538 |
| 12 | 330058 |
| 13 | 2133438 |
| 14 | 11192143 |
| 15 | 73469550 |
| 16 | 462692414 |
| 17 | 3692965270 |
| 18 | 32635321384 |
| 19 | 290171883863 |
| 20 | 2572828730372 |
| 21 | 22299380503953 |
| 22 | 195129375058656 |
| 23 | 1544534855847233 |
| 24 | 13144353749969945 |
| 25 | 128883813733449772 |
| 26 | 1365629506139662111 |