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 | 3 |
| 1 | 18 |
| 2 | 122 |
| 3 | 882 |
| 4 | 6578 |
| 5 | 49818 |
| 6 | 380522 |
| 7 | 2922882 |
| 8 | 22548578 |
| 9 | 174591018 |
| 10 | 1356276122 |
| 11 | 10567438482 |
| 12 | 82561295378 |
| 13 | 646646418618 |
| 14 | 5076274366922 |
| 15 | 39931947947682 |
| 16 | 314707950326978 |
| 17 | 2484430456812618 |
| 18 | 19642812494812922 |
| 19 | 155514084423490482 |