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 | 1 |
| 2 | 3 |
| 3 | 15 |
| 4 | 91 |
| 5 | 641 |
| 6 | 5147 |
| 7 | 46433 |
| 8 | 465081 |
| 9 | 5121789 |
| 10 | 61513799 |
| 11 | 800196799 |
| 12 | 11208394387 |
| 13 | 168193068805 |
| 14 | 2691956450679 |
| 15 | 45775335405729 |
| 16 | 824136306116113 |
| 17 | 15661462041469817 |
| 18 | 313277888390065739 |
| 19 | 6579708440058166031 |