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 | 15 |
| 3 | 107 |
| 4 | 991 |
| 5 | 11203 |
| 6 | 148879 |
| 7 | 2270027 |
| 8 | 39041151 |
| 9 | 747704963 |
| 10 | 15784630159 |
| 11 | 364256650027 |
| 12 | 9124264794271 |
| 13 | 246600188525123 |
| 14 | 7153677209063439 |
| 15 | 221729176945261067 |
| 16 | 7313478624348963391 |
| 17 | 255786689421734222083 |