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) |
|---|---|
| 3 | 1 |
| 4 | 3 |
| 5 | 18 |
| 6 | 131 |
| 7 | 1180 |
| 8 | 12570 |
| 9 | 154525 |
| 10 | 2150748 |
| 11 | 33399546 |
| 12 | 571979428 |
| 13 | 10699844995 |
| 14 | 216921707622 |
| 15 | 4734437392728 |
| 16 | 110613829184421 |
| 17 | 2752971531611715 |
| 18 | 72676980383698345 |
| 19 | 2027560176161932735 |
| 20 | 59579981648921326791 |
| 21 | 1838669555339295257097 |
| 22 | 59435431024069408426431 |