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 | 117 |
| 4 | 1785 |
| 5 | 29799 |
| 6 | 527085 |
| 7 | 9706503 |
| 8 | 184138713 |
| 9 | 3573805950 |
| 10 | 70625252863 |
| 11 | 1416298046436 |
| 12 | 28748759731965 |
| 13 | 589546754316126 |
| 14 | 12195537924351375 |
| 15 | 254184908607118800 |
| 16 | 5332692942907262361 |