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 | 1 |
| 3 | 1 |
| 4 | 9 |
| 5 | 121 |
| 6 | 17161 |
| 7 | 33189121 |
| 8 | 9112869675009 |
| 9 | 4839170130591864288001 |
| 10 | 705579627764469400107962287271157001 |
| 11 | 54630717750911142085059359537536676834981970103054482555001 |