

A319900


a(n) is the number of distinct ways to arrange n copies of each of the numbers 1 through n^2 inside a fixed n X n X n cube, provided that no number appears twice in the same leftright plane, frontback plane, or topbottom plane.


1




OFFSET

1,2


COMMENTS

When n = 3, this is equivalent to enumerating the different fillins of a SudoKurve puzzle of the shape given in the link 'SudoKurve 38'.


LINKS



FORMULA



EXAMPLE

For n = 2, the top layer of the 2 X 2 X 2 cube must contain each of the numbers 1, 2, 3, 4. This can be arranged in 24 ways. Each way uniquely determines the rest of the cube, so there are 24 possible cubes.


CROSSREFS



KEYWORD

bref,nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



