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Signed Involutions Avoiding 2-Letter Signed Patterns
W.M.B. Dukes1 and Toufik Mansour2
1Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavík, Iceland
2Department of Mathematics, Faculty of Science and Science Education, University of Haifa, Haifa 31905, Israel
Annals of Combinatorics 11 (3-4) p.387-403 September, 2007
AMS Subject Classification:05A15, 05A05
Let In be the class of all signed involutions in the hyperoctahedral group Bn and let In(T) be the set of involutions in In which avoid a set T of signed patterns. In this paper, we complete a further case of the program initiated by Simion and Schmidt [6] by enumerating In(T) for all signed permutations T B2.
Keywords: pattern avoidance, signed patterns, involutions


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