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 | 12 |
| 2 | 162 |
| 3 | 3750 |
| 4 | 28812 |
| 5 | 439230 |
| 6 | 1199562 |
| 7 | 6013512 |
| 8 | 11728890 |
| 9 | 36939012 |
| 10 | 148529010 |
| 11 | 221645040 |
| 12 | 640963062 |
| 13 | 1186819620 |
| 14 | 1579486062 |
| 15 | 2693583912 |
| 16 | 5539117662 |
| 17 | 10542104070 |
| 18 | 12876632130 |
| 19 | 22609557762 |
| 20 | 32018718060 |
| 21 | 37826457012 |