Isomorphisms between pattern classes
نویسندگان
چکیده
منابع مشابه
Generating-tree isomorphisms for pattern-avoiding involutions∗
We show that for k ≥ 5 and the permutations τk = (k − 1)k(k − 2) . . . 312 and Jk = k(k − 1) . . . 21, the generating tree for involutions avoiding the pattern τk is isomorphic to the generating tree for involutions avoiding the pattern Jk. This implies a family of Wilf equivalences for pattern avoidance by involutions; at least the first member of this family cannot follow from any type of pre...
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ژورنال
عنوان ژورنال: Journal of Combinatorics
سال: 2015
ISSN: 2156-3527,2150-959X
DOI: 10.4310/joc.2015.v6.n1.a1