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) |
|---|---|
| 2 | 30 |
| 3 | 348 |
| 4 | 3459 |
| 5 | 33145 |
| 6 | 316164 |
| 7 | 3013590 |
| 8 | 28722567 |
| 9 | 273751765 |
| 10 | 2609096478 |
| 11 | 24866992602 |
| 12 | 237004387635 |
| 13 | 2258860992595 |
| 14 | 21528938911842 |
| 15 | 205189789087374 |
| 16 | 1955639788756293 |
| 17 | 18638973217791295 |
| 18 | 177645865363829526 |
| 19 | 1693121885638023396 |
| 20 | 16136945905019298321 |
| 21 | 153799336805212613275 |