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 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 1 |
| 7 | 5 |
| 8 | 16 |
| 9 | 66 |
| 10 | 266 |
| 11 | 1235 |
| 12 | 6350 |
| 13 | 37364 |
| 14 | 251106 |
| 15 | 1942085 |
| 16 | 17287710 |
| 17 | 177086792 |
| 18 | 2084120446 |
| 19 | 28125888087 |
| 20 | 434318629496 |
| 21 | 7657513894860 |