Truncated Permutations

Combinatorics, Truncated Permutations

Truncated Permutations

When only the first k elements of an n-element permutation are significant, the number of unique permutations is n!/(n-k)!. As before, there are n elements to choose from, then n-1, then n-2, down to n-k+1. This product is n!/(n-k)!.