Annals of Combinatorics 7(2003) 1-14

Alexander Burstein and Toufik Mansour

Department of Mathematics, Iowa State University, Ames, IA 50011-2064, USA
burstein@math.iastate.edu

Department of Mathematics, Chalmers Univeristy of Technology, 412~96 GÖteborg, Sweden
toufik@math.chalmers.se

Received November 20, 2002

AMS Subject Classification: 05A05, 05A15

Abstract. We find exact formulas and/or generating functions for the number of words avoiding 3-letter generalized multipermutation patterns and find which of them are equally avoided.

Keywords: k-ary words, generalized patterns, generating functions

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