Permutation meaning and example

what is the permutation?
and like what example?
anyone knows?

HallsofIvy
Homework Helper
Do you mean "what is a permutation"? A permutation of a given list is simply a rearrangement of the list. For example, if the original list is "abc" then permutations are "acb", "bac", "bca", "cab", "cba", and, for completeness, we include the orignal list, "abc" as a permutation.

i see,
so its just rearrange the list into random right?

I like Serena
Homework Helper
Formally, a permutation is a 1-1 map of a set onto itself.

phinds
Gold Member
2019 Award
i see,
so its just rearrange the list into random right?
No, it is NOT random. It is a set of all possible arrangements.

For combinations, on the other hand, order does not matter, so the combinations of abc are abc OR bca OR cab, etc --- but they are all counted as the same thing.

we can define permutation as-
1.NUMBER OF ORDERED SELECTION OF "K" OBJECTS OUT OF "N" DISTINCT OBJECTS WITHOUT REPETITION.OR.;
2.ORDERED SAMPLING OF K OBJECTS OUT OF N DISTINCT OBJECTS WITHOUT REPLACEMENT.OR
3.NUMBER OF PERMUTATION(ORDERED SAMPLING)OF K OBJECTS OUT OF N DISTINCT OBJECTS WITHOUT REPETATION...