How does the Derangements Calculator work?

Identify number of items (n) Then: Calculate factorial of n Then: Apply derangement formula Then: Use for seat arrangement, gift exchange problems.

Can you give an example of how to use the Derangements Calculator?

Example: Input n = 4 gives a result of D(4) = 9 (Number of ways 4 people can exchange gifts so nobody gets theirs).

Is the Derangements Calculator free to use?

Yes — completely free with no registration, download, or subscription required. All calculations happen instantly in your browser.

How accurate is the Derangements Calculator?

Our Derangements Calculator uses verified mathematical formulas and is accurate to multiple decimal places. Results are calculated in real-time using the same methods used by professionals.

Matemáticas

Derangements Calculator

Calculates derangements (permutations with no fixed points).

Difficulty:advanced

References

›Derangements Calculator — Wikipedia

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Derangements Calculator

Qué es Derangements Calculator?

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Cómo Derangements Calculator

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