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 | 3 |
| 2 | 21 |
| 3 | 231 |
| 4 | 3465 |
| 5 | 65835 |
| 6 | 1514205 |
| 7 | 40883535 |
| 8 | 1267389585 |
| 9 | 44358635475 |
| 10 | 1729986783525 |
| 11 | 74389431691575 |
| 12 | 3496303289504025 |
| 13 | 178311467764705275 |
| 14 | 9807130727058790125 |
| 15 | 578620712896468617375 |
| 16 | 36453104912477522894625 |
| 17 | 2442358029135994033939875 |