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 | 9 |
| 2 | 137 |
| 3 | 2697 |
| 4 | 60041 |
| 5 | 1436297 |
| 6 | 36039305 |
| 7 | 935717513 |
| 8 | 24927136393 |
| 9 | 677493729929 |
| 10 | 18712061405833 |
| 11 | 523679956331145 |
| 12 | 14818155751139977 |
| 13 | 423231749888535177 |
| 14 | 12185543261045516937 |
| 15 | 353292577084597987977 |
| 16 | 10305591916877658319497 |