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TCS
2008
13 years 10 months ago
Simple permutations: Decidability and unavoidable substructures
We prove that it is decidable whether a finitely based permutation class contains infinitely many simple permutations, and establish an unavoidable substructure result for simple ...
Robert Brignall, Nikola Ruskuc, Vincent Vatter
COMBINATORICS
2007
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13 years 11 months ago
Wreath Products of Permutation Classes
A permutation class which is closed under pattern involvement may be described in terms of its basis. The wreath product construction X Y of two permutation classes X and Y is als...
Robert Brignall
CORR
2010
Springer
95views Education» more  CORR 2010»
13 years 11 months ago
Deciding the finiteness of the number of simple permutations contained in a wreath-closed class is polynomial
We present an algorithm running in time O(n log n) which decides if a wreathclosed permutation class Av(B) given by its finite basis B contains a finite number of simple permutati...
Frédérique Bassino, Mathilde Bouvel,...