Counting Types of Runs in Classes of Arborescent Words


An arborescence is a directed rooted tree in which all edges point away from the root. An arborescent word is obtained by replacing each element of the underlying set of an arborescence by an arbitrary letter of a given alphabet (with possible repetitions). We define a run in an arborescent word as a maximal sub-arborescent word whose letters are all identical. Various types of runs (e.g., runs of sizek, linear runs, etc) are studied in the context of R-enriched arborescent words, where R is a given species of structures.

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J. Labbé and G. Labelle, "Counting Types of Runs in Classes of Arborescent Words," Open Journal of Discrete Mathematics, Vol. 3 No. 1, 2013, pp. 7-15. doi: 10.4236/ojdm.2013.31002.

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The authors declare no conflicts of interest.


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