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 | 9 |
| 1 | 17 |
| 2 | 89 |
| 3 | 737 |
| 4 | 6569 |
| 5 | 59057 |
| 6 | 531449 |
| 7 | 4782977 |
| 8 | 43046729 |
| 9 | 387420497 |
| 10 | 3486784409 |
| 11 | 31381059617 |
| 12 | 282429536489 |
| 13 | 2541865828337 |
| 14 | 22876792454969 |
| 15 | 205891132094657 |
| 16 | 1853020188851849 |
| 17 | 16677181699666577 |
| 18 | 150094635296999129 |
| 19 | 1350851717672992097 |
| 20 | 12157665459056928809 |