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 | 0 |
| 1 | 14 |
| 2 | 48 |
| 3 | 254 |
| 4 | 1824 |
| 5 | 13742 |
| 6 | 102096 |
| 7 | 745502 |
| 8 | 5374272 |
| 9 | 38400590 |
| 10 | 272709744 |
| 11 | 1928498750 |
| 12 | 13597146720 |
| 13 | 95668307438 |
| 14 | 672119557392 |
| 15 | 4717043931998 |
| 16 | 33080342679168 |
| 17 | 231867574534286 |
| 18 | 1624598900645040 |
| 19 | 11379821699045246 |