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 | 13 |
| 4 | 97 |
| 5 | 997 |
| 6 | 13585 |
| 7 | 225625 |
| 8 | 4454801 |
| 9 | 101415881 |
| 10 | 2618639033 |
| 11 | 75524367593 |
| 12 | 2406745316697 |
| 13 | 83950853842617 |
| 14 | 3181371937414425 |
| 15 | 130135485102246265 |
| 16 | 5714800778645325881 |
| 17 | 268144898273200109561 |
| 18 | 13387708871579930596793 |
| 19 | 708640690235801235876153 |