# Problem 559: Permuted Matrices
An ascent of a column j in a matrix occurs if the value of column j is
smaller than the value of column j+1 in all rows. Let P(k, r, n) be the
number of r x n matrices with the following properties: The rows are
permutations of {1, 2, 3, ... , n}. Numbering the first column as 1, a
column ascent occurs at column j