• Corpus ID: 15145564

Pattern avoidance in labelled trees

  title={Pattern avoidance in labelled trees},
  author={Vladimir Dotsenko},
  journal={arXiv: Combinatorics},
  • V. Dotsenko
  • Published 4 October 2011
  • Mathematics
  • arXiv: Combinatorics
We discuss a new notion of pattern avoidance motivated by the operad theory: pattern avoidance in planar labelled trees. It is a generalisation of various types of consecutive pattern avoidance studied before: consecutive patterns in words, permutations, coloured permutations etc. The notion of Wilf equivalence for patterns in permutations admits a straightforward generalisation for (sets of) tree patterns; we describe classes for trees with small numbers of leaves, and give several bijections… 
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