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 | 18 |
| 4 | 157 |
| 5 | 1812 |
| 6 | 25989 |
| 7 | 445255 |
| 8 | 8865333 |
| 9 | 201058614 |
| 10 | 5114874693 |
| 11 | 144207579708 |
| 12 | 4462151144553 |
| 13 | 150316762118466 |
| 14 | 5475746846833734 |
| 15 | 214463847533104125 |
| 16 | 8986421286160678944 |
| 17 | 401112805593137715609 |
| 18 | 18999650382886046745879 |