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 | 9 |
| 3 | 108 |
| 4 | 1000 |
| 5 | 1012500 |
| 6 | 15552 |
| 7 | 25015118625000 |
| 8 | 17757684573750000 |
| 9 | 19699405917187500 |
| 10 | 295491088757812500 |
| 11 | 2754030502015722328328015625000 |
| 12 | 69471494082638078965978431093750000 |