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 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 15 |
| 6 | 15 |
| 7 | 1605 |
| 8 | 1605 |
| 9 | 19425 |
| 10 | 2397347205 |
| 11 | 153535525935 |
| 12 | 29503289812425 |
| 13 | 29503289812425 |
| 14 | 32467505340816975 |
| 15 | 143924005810811655 |
| 16 | 143924005810811655 |