In mathematics, the notion of permutation relates to the act of arranging all the members of a set into some sequence or order, or if the set is already ordered, rearranging (reordering) its elements, a process called permuting.
Alice, Bob and Charlie is different from Charlie, Bob and Alice [2]
permutations, or all possible ways of doing something [2]
Permutations with Repetition [3]
Given a set: P { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }
How many ways can we choose any 3 elements from the set? (You can select the same element for each selection)
If n is the number of elements in the set, we can always choose n possible ways for each selection.
If r is the number of selections, the total number of permutations would be n x n x n...r number of times or nr
Permutations without Repetition
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