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 | 15 |
| 2 | 225 |
| 3 | 1071 |
| 4 | 7289 |
| 5 | 44121 |
| 6 | 279219 |
| 7 | 1737981 |
| 8 | 10873197 |
| 9 | 67902955 |
| 10 | 424387041 |
| 11 | 2651860269 |
| 12 | 16571735565 |
| 13 | 103552803445 |
| 14 | 647076103565 |
| 15 | 4043412030973 |
| 16 | 25266419946873 |
| 17 | 157884983254865 |
| 18 | 986593269768561 |
| 19 | 6165025417156933 |