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 | 2 |
| 3 | 18 |
| 4 | 196 |
| 5 | 2500 |
| 6 | 33896 |
| 7 | 476270 |
| 8 | 6849777 |
| 9 | 100203194 |
| 10 | 1485200848 |
| 11 | 22245940545 |
| 12 | 336093325058 |
| 13 | 5114451441106 |
| 14 | 78306011677182 |
| 15 | 1205243866707468 |
| 16 | 18635412907198670 |
| 17 | 289296535756895985 |
| 18 | 4506983054619138245 |
| 19 | 70436637624668665265 |