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 | 13 |
| 2 | 289 |
| 3 | 5185 |
| 4 | 82945 |
| 5 | 1244161 |
| 6 | 17915905 |
| 7 | 250822657 |
| 8 | 3439853569 |
| 9 | 46438023169 |
| 10 | 619173642241 |
| 11 | 8173092077569 |
| 12 | 106993205379073 |
| 13 | 1390911669927937 |
| 14 | 17974858503684097 |
| 15 | 231105323618795521 |
| 16 | 2958148142320582657 |
| 17 | 37716388814587428865 |
| 18 | 479219999055934390273 |
| 19 | 6070119988041835610113 |