DerangementQ[p] tests whether permutation p is a derangement, that is, a permutation without a fixed point.

Derangements[p] constructs all derangements of permutation p.

DistinctPermutations[l] gives all permutations of the multiset described by list l.

Distribution[l, set] lists the frequency of each element of set in list l.

EmptyQ[g] yields True if graph g contains no edges.

EncroachingListSet[p] constructs the encroaching list set associated with permutation p.

EquivalenceClasses[r] identifies the equivalence classes among the elements of matrix r.

EulerianCycle[g] finds an Eulerian cycle of g if one exists.

Eulerian[n, k] gives the number of permutations of length n with k runs.

ExactRandomGraph[n, e] constructs a random labeled graph of exactly e edges and n vertices.