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 | 7 |
| 4 | 22 |
| 5 | 85 |
| 6 | 330 |
| 7 | 1433 |
| 8 | 6450 |
| 9 | 31555 |
| 10 | 172023 |
| 11 | 964560 |
| 12 | 5891154 |
| 13 | 37807505 |
| 14 | 248226019 |
| 15 | 1702890101 |
| 16 | 12401685616 |
| 17 | 95277158949 |
| 18 | 744210074157 |
| 19 | 6091922351106 |
| 20 | 51332717836692 |
| 21 | 438592279944173 |
| 22 | 3898316990125822 |
| 23 | 35515462315592564 |
| 24 | 335052677538616216 |
| 25 | 3299888425002527366 |