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 | 3 |
| 3 | 6 |
| 4 | 18 |
| 5 | 58 |
| 6 | 221 |
| 7 | 935 |
| 8 | 4361 |
| 9 | 22082 |
| 10 | 120336 |
| 11 | 700652 |
| 12 | 4333933 |
| 13 | 28345089 |
| 14 | 195233255 |
| 15 | 1411303634 |
| 16 | 10675375402 |
| 17 | 84276173438 |
| 18 | 692752181561 |
| 19 | 5917018378495 |
| 20 | 52416910416933 |
| 21 | 480786834535246 |
| 22 | 4559132648864256 |
| 23 | 44632792689619592 |
| 24 | 450518001943669545 |