How this calculator works
Permutations use P(n,r)=n!/(n−r)! and count arrangements where order matters.
Formula
P(n,r)=n!/(n−r)!Counts ordered selections of r objects from n distinct objects without replacement.
Worked example
Five choose three in order is a verified test case used by the calculation engine.
Assumptions and limitations
- n and r are non-negative integers with r≤n.
- Objects are distinct and selections are made without replacement.
- Results are limited to the supported exact integer range.
Methodology & sources
This calculator uses deterministic, versioned calculation logic. The formula and verified examples above are part of the calculation definition used by CalcuMint. Technical calculation version: 1.
- CalcuMint deterministic statistics engine
Frequently asked questions
When should I use permutations instead of combinations?
Use permutations when the order of selected objects matters.
What is P(n,0)?
There is one ordered selection of zero objects, so P(n,0)=1.