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 | 1 |
| 1 | 3 |
| 2 | 49 |
| 3 | 459 |
| 4 | 3913 |
| 5 | 39507 |
| 6 | 363169 |
| 7 | 3421083 |
| 8 | 32375353 |
| 9 | 303697827 |
| 10 | 2862955537 |
| 11 | 26952847467 |
| 12 | 253686746665 |
| 13 | 2388861601779 |
| 14 | 22489001385601 |
| 15 | 211729323587643 |
| 16 | 1993409453728537 |
| 17 | 18767289570726723 |
| 18 | 176690276990149105 |