Discrete Mathematics, Discrete Maths, Combinatorics, Permutations, Graph Theory.
regard to order. For example, the combinations of the set {1, 2, 3} are {1, 2}, {1, 3}, {2, 3}, {1}, {2}, and {3}. The set of combinations is never the same. Once we count {1, 2}, we do not count {2, 1}. Permutations and Combinations In short, permutations take into account the order of the