Combination Sum Calculator

Calculate the number of combinations possible for given set sizes.

About

The combination sum calculator allows you to determine the number of ways to choose a subset of items from a larger set. This is useful in fields like statistics, probability, and combinatorics where you need to calculate possible selections.

The formula to calculate combinations is:

C(n, r) = n! / (r! * (n-r)!)

Quick Reference

n r C(n, r)
5 2 10
6 3 20
10 4 210
8 2 28
7 5 21

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