Abstract
We give a new elementary proof of El Sahili conjecture El Sahili (Discrete Math 287:151–153, 2004) stating that any n-chromatic digraph D, with \(n\ge 4\), contains a path with two blocks of order n.
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El Sahili, A., Mortada, M. & Nasser, S. The Existence of a Path with Two Blocks in Digraphs. Graphs and Combinatorics 40, 34 (2024). https://doi.org/10.1007/s00373-024-02759-8
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DOI: https://doi.org/10.1007/s00373-024-02759-8