Combinações c/ Repetição
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
The Combination with Repetition Calculator is an online tool that calculates the number of possible combinations of a set of elements, allowing elements to be repeated. It uses the mathematical formula (n+r−1)!/(r!(n−1)!), where n is the number of types of elements and r is the number of elements to be chosen.
This formula works by calculating the total number of possible combinations with the inclusion of repeated elements. It is especially useful in situations where the order of elements is not important and elements can be chosen more than once. For example, when choosing 3 cakes from a set of 5 types of cakes, the calculator can determine how many different combinations exist.
Combinations with repetition are common in combinatorial problems and are applied in various fields, such as statistics, probability, and data analysis. They are useful for solving problems that involve choosing samples with replacement.
When using the calculator, it is essential to be careful with the input values, ensuring that n and r are positive integers. Additionally, it is crucial to understand the context of the problem to correctly apply the formula and interpret the results.
Frequently asked questions
What is a combination with repetition?
A combination with repetition is a selection of elements from a set, where elements can be repeated and the order is not important.
When to use the combination with repetition formula?
Use the formula when you need to choose elements from a set and elements can be repeated, such as in sampling problems with replacement.
How to interpret the calculator result?
The result represents the total number of possible combinations of elements, considering repetitions.
What are the restrictions for input values?
The values of n and r must be positive integers.
Can the calculator be used for large-scale problems?
Yes, the calculator can handle large-scale problems, but it is essential to check computational limits for very large values of n and r.