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Intuition behind permutations and combinations (2016) (buildingvts.com)
74 points by smithsmith on July 12, 2017 | hide | past | favorite | 3 comments



I remember reading this excellent little book with very easy to understand explanations of some of the basics re. permutations and combinations, back in school:

"Mathematics of Choice: How to Count Without Counting" by Ivan Morton Niven

https://www.amazon.com/Mathematics-Choice-New-Mathematical-L...


Why do we need this? What's wrong with good old "there are n ways to pick first element, n-1 ways to pick second, etc and then apply burnside to glue together things that we treat as identical"?


Wow. very different and useful mental model to think combinations and permutations.




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