### Abstract

The Derangements Formula describes the number of fixpoint-free permutations as a closed formula. This theorem is the 88th theorem in a list of the “Top 100 Mathematical Theorems”.

### License

BSD License

### Topics

- Mathematics/Combinatorics

### Session Derangements

- Derangements

## Cite

×

Derangements-AFP

    @article{Derangements-AFP,
      author  = {Lukas Bulwahn},
      title   = {Derangements Formula},
      journal = {Archive of Formal Proofs},
      month   = {June},
      year    = {2015},
      note    = {\url{https://isa-afp.org/entries/Derangements.html},
                 Formal proof development},
      ISSN    = {2150-914x},
    }

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