Two examples of unbalanced Wilf-equivalence
نویسندگان
چکیده
منابع مشابه
Egge triples and unbalanced Wilf equivalence
Egge, in a talk at the AMS Fall Eastern Meeting, 2012, conjectured that permutations avoiding the set of patterns {2143, 3142, τ}, where τ ∈ {246135, 254613, 524361, 546132, 263514}, are enumerated by the large Schröder numbers (and thus {2143, 3142, τ} with τ as above is Wilfequivalent to the set of patterns {2413, 3142}). Burstein and Pantone [J. Combin. 6 (2015) no. 1-2, 55–67] proved the ca...
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Consider the alphabet A and define A∗ as the set of words over A. Define a vector of sequences of subsets of N as ~u = (u1, u2, . . . , uk). Consider a word w ∈ A∗. Define their to be an embedding of ~u in w, ~u ≤ w if there is some i such that, wi ∈ uj , wi+1 ∈ uj+1, . . . wi+k−1 ∈ uj+k−1. Define a word that avoids the vector ~u as a word where there is no such i, such that wi ∈ uj , wi+1 ∈ uj...
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ژورنال
عنوان ژورنال: Journal of Combinatorics
سال: 2015
ISSN: 2156-3527,2150-959X
DOI: 10.4310/joc.2015.v6.n1.a4