HasseDiagram[g] constructs a Hasse diagram of the relation defined by directed acyclic graph g.

HeapSort[l] performs a heap sort on the items of list l.

IntervalGraph[l] constructs the interval graph defined by the list of intervals l.

InversePermutation[p] yields the multiplicative inverse of permutation p.

Inversions[p] counts the number of inversions in permutation p.

LexicographicPermutations[l] constructs all permutations of list l in lexicographic order.

LineGraph[g] constructs the line graph of graph g.

LongestIncreasingSubsequence[p] finds the longest increasing scattered subsequence of permutation p.

MakeSimple[g] gives the undirected graph, free of multiple edges and self-loops derived from graph g.

MaximumAntichain[g] gives a largest set of unrelated vertices in partial order g.