Without repetition

Combination generator without repetition.

Use combinations without repetition when each value can be selected at most once inside the same result.

Default behavior

In ComboKit Studio, leave “Allow repeats inside a result” unchecked to generate combinations without repetition.

Open the generator

Example

If the source values are A, B, C and the group size is 2, valid combinations are:

A · B
A · C
B · C

Results such as A · A are not allowed because A would be repeated inside the same result.

Use cases

  • Choosing unique team members from a roster.
  • Creating test input pairs where each value should appear once per row.
  • Listing possible selections from codes, labels, or product options.

How the count works

For combinations without repetition, the count is usually written as C(n, r), where n is the number of available items and r is the group size.

Calculate the exact nCr count

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