Documentation

Pattern is just an alias for permutation.

A set is represented by an increasing array of non-negative integers.

ordiso u v m determines whether the subword in v specified by m is order isomorphic to u.

subsets n k is the list of subsets of [0..n-1] with k elements.

copies p w is the list of sets that represent copies of p in w.

w contains p is a predicate determining if w contains the pattern p.

w avoids p is a predicate determining if w avoids the pattern p.

w avoidsAll ps is a predicate determining if w avoids the patterns ps.

avoiders ps ws is the list of permutations in ws avoiding the patterns in ps.

The set of minimal elements with respect to containment.

The set of maximal elements with respect to containment.

coeff f v is the coefficient of v when expanding the permutation statistic f as a sum of permutations/patterns. See Petter Brändén and Anders Claesson: Mesh patterns and the expansion of permutation statistics as sums of permutation patterns, The Electronic Journal of Combinatorics 18(2) (2011), http://www.combinatorics.org/ojs/index.php/eljc/article/view/v18i2p5.