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 | 3 |
| 3 | 9 |
| 4 | 21 |
| 5 | 81 |
| 6 | 147 |
| 7 | 729 |
| 8 | 903 |
| 9 | 3025 |
| 10 | 6875 |
| 11 | 59049 |
| 12 | 29095 |
| 13 | 531441 |
| 14 | 171875 |
| 15 | 366025 |
| 16 | 643885 |
| 17 | 43046721 |
| 18 | 3511475 |