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 | 339 |
| 4 | 44521 |
| 5 | 19059921 |
| 6 | 25799597265 |
| 7 | 108657870607875 |
| 8 | 1410396873934264497 |
| 9 | 56078100848527445045121 |
| 10 | 6801233273726638573734096441 |
| 11 | 2508450630100541880792088526933139 |