2 citations · 3 across the 6 of their papers we have counts for
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Griddings of permutations and hardness of pattern matching
Vít Jelínek, Michal Opler, Jakub Pekárek
We study the complexity of the decision problem known as Permutation Pattern Matching, or PPM. The input of PPM consists of a pair of permutations (the `text') and (the `pa…
A Complexity Dichotomy for Permutation Pattern Matching on Grid Classes
Vít Jelínek, Michal Opler, Jakub Pekárek
Permutation Pattern Matching (PPM) is the problem of deciding for a given pair of permutations P and T whether the pattern P is contained in the text T. Bose, Buss and Lubiw showed…
Fillings of skew shapes avoiding diagonal patterns
Vít Jelínek, Mark Karpilovskij
A skew shape is the difference of two top-left justified Ferrers shapes sharing the same top-left corner. We study integer fillings of skew shapes. As our first main result, we sho…
Two examples of Wilf-collapse
Michael Albert, Vít Jelínek, Michal Opler
Two permutation classes, the X-class and subpermutations of the increasing oscillation are shown to exhibit an exponential Wilf-collapse. This means that the number of distinct enu…
Wilf collapse in permutation classes
Michael Albert, Vít Jelínek, Michal Opler
For a hereditary permutation class , we say that two permutations and of are Wilf-equivalent in , if has the same numb…
Zeros of the Möbius function of permutations
Robert Brignall, Vít Jelínek, Jan Kynčl +1
We show that if a permutation contains two intervals of length 2, where one interval is an ascent and the other a descent, then the Möbius function of the interval $[1,π…