# Permutations and combinations

This English edition is an AI candidate and does not yet have an OCME Atlas (GPT-6) Twin closure receipt.

[Catalogue presentation and source-binding data](https://ocme.evemisslab.com/data/i18n/catalogue.en.json)



## [Permutations and combinations](https://ocme.evemisslab.com/en/atlas/atlas-permutation-combination/)

When k distinct objects are selected without replacement from n distinct objects, an ordered selection is a permutation and an unordered selection is a combination.

atlas-permutation-combination · canonical_mko

[Permutations and combinations](https://ocme.evemisslab.com/en/mko/mko-permutation-combination/)

## Prerequisite nodes


- [Basic counting principles](https://ocme.evemisslab.com/en/atlas/atlas-counting-principle/)
- [Factorial](https://ocme.evemisslab.com/en/atlas/atlas-factorial/)