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 | 11 |
| 3 | 67 |
| 4 | 460 |
| 5 | 3532 |
| 6 | 30225 |
| 7 | 286289 |
| 8 | 2979896 |
| 9 | 33852226 |
| 10 | 417123475 |
| 11 | 5543942107 |
| 12 | 79086006756 |
| 13 | 1205573749892 |
| 14 | 19561113090785 |
| 15 | 336643494142657 |
| 16 | 6125614986385360 |
| 17 | 117514626855080914 |
| 18 | 2370682022353448571 |
| 19 | 50173196512398036851 |
| 20 | 1111614380526424428380 |