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 | 2 |
| 2 | 9 |
| 3 | 61 |
| 4 | 550 |
| 5 | 6195 |
| 6 | 83837 |
| 7 | 1326923 |
| 8 | 24078588 |
| 9 | 493309850 |
| 10 | 11271757335 |
| 11 | 284379843234 |
| 12 | 7856320956198 |
| 13 | 235986714918110 |
| 14 | 7660827258318780 |
| 15 | 267365373971139600 |
| 16 | 9985779421324740445 |
| 17 | 397508459931685273305 |