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 | 1 |
| 2 | 9 |
| 3 | 153 |
| 4 | 3825 |
| 5 | 126225 |
| 6 | 5175225 |
| 7 | 253586025 |
| 8 | 14454403425 |
| 9 | 939536222625 |
| 10 | 68586144251625 |
| 11 | 5555477684381625 |
| 12 | 494437513909964625 |
| 13 | 47960438849266568625 |
| 14 | 5035846079172989705625 |
| 15 | 569050606946547836735625 |
| 16 | 68855123440532288245010625 |
| 17 | 8882310923828665183606370625 |