Tree Counting

Let's define a good tree: - It is a tree with k * n nodes labeled from 0 to k * n - 1 - Node i and node j are not adjacent, for all 0 such that i div k = j div k (here div means integer division. E.g. 7 div 2 = 3) Given n and k, how many different good trees are there? Input Two integers n(1 Output Output the number of different good trees. As the result may be very large, just output the re