Discrete Mathematics, Discrete Maths, Combinatorics, Permutations, Graph Theory.
{1, 2, 3} are {1, 2, 3}, {1, 3, 2}, {2, 1, 3}, {2, 3, 1}, {3, 1, 2}, and {3, 2, 1}. The set is the same, the order changes, and we count how many ways we can arrange the same set of three numbers. Combinations, on the other hand, are the number of ways that a set of items can be selected without