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 | 81 |
| 3 | 4409 |
| 4 | 175720 |
| 5 | 2479881 |
| 6 | 17925691 |
| 7 | 92952858 |
| 8 | 379978716 |
| 9 | 1286959255 |
| 10 | 3765248749 |
| 11 | 9805497200 |
| 12 | 23226916560 |
| 13 | 50866495373 |
| 14 | 104288896551 |
| 15 | 202154535834 |
| 16 | 373400685738 |
| 17 | 661407061211 |
| 18 | 1129334088897 |
| 19 | 1866838857216 |