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 | 2 |
| 2 | 3 |
| 3 | 6 |
| 4 | 15 |
| 5 | 42 |
| 6 | 131 |
| 7 | 432 |
| 8 | 1497 |
| 9 | 5420 |
| 10 | 20373 |
| 11 | 79422 |
| 12 | 319927 |
| 13 | 1328764 |
| 14 | 5677653 |
| 15 | 24904584 |
| 16 | 111961129 |
| 17 | 515029020 |
| 18 | 2421047613 |
| 19 | 11616330342 |
| 20 | 56829235095 |
| 21 | 283211069352 |
| 22 | 1436529522233 |
| 23 | 7410596379456 |
| 24 | 38852645340297 |