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 | 2 |
| 2 | 14 |
| 3 | 84 |
| 4 | 462 |
| 5 | 2418 |
| 6 | 12252 |
| 7 | 60666 |
| 8 | 295230 |
| 9 | 1417452 |
| 10 | 6732102 |
| 11 | 31690914 |
| 12 | 148080468 |
| 13 | 687592338 |
| 14 | 3175567374 |
| 15 | 14597507076 |
| 16 | 66827528094 |
| 17 | 304831251762 |
| 18 | 1386004252620 |
| 19 | 6283722000714 |
| 20 | 28414577975934 |
| 21 | 128187044049948 |
| 22 | 577056144993366 |