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 | 6 |
| 2 | 18 |
| 3 | 55 |
| 4 | 174 |
| 5 | 548 |
| 6 | 1733 |
| 7 | 5478 |
| 8 | 17321 |
| 9 | 54773 |
| 10 | 173206 |
| 11 | 547723 |
| 12 | 1732051 |
| 13 | 5477226 |
| 14 | 17320509 |
| 15 | 54772256 |
| 16 | 173205081 |
| 17 | 547722558 |
| 18 | 1732050808 |
| 19 | 5477225576 |
| 20 | 17320508076 |
| 21 | 54772255751 |
| 22 | 173205080757 |
| 23 | 547722557506 |
| 24 | 1732050807569 |
| 25 | 5477225575052 |
| 26 | 17320508075689 |
| 27 | 54772255750517 |