The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 12 |
| 3 | 330 |
| 4 | 14300 |
| 5 | 831402 |
| 6 | 59491432 |
| 7 | 4971783960 |
| 8 | 468842704200 |
| 9 | 48707547603000 |
| 10 | 5478624954385440 |
| 11 | 658555622357831640 |
| 12 | 83752779737507765040 |
| 13 | 11180459218164097480500 |
| 14 | 1556759031871924444410000 |
| 15 | 224927463853886185614776400 |
| 16 | 33579302695870956078753329400 |
| 17 | 5161336349665341660810732336600 |
[1,1,12,330,14300,831402,59491432,4971783960, 468842704200,48707547603000,5478624954385440, 658555622357831640,83752779737507765040, 11180459218164097480500,1556759031871924444410000, 224927463853886185614776400, 33579302695870956078753329400, 5161336349665341660810732336600] |