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Using edge contractions to reduce the semitotal domination number

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 نشر من قبل Paloma Thome De Lima
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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In this paper, we consider the problem of reducing the semitotal domination number of a given graph by contracting $k$ edges, for some fixed $k geq 1$. We show that this can always be done with at most 3 edge contractions and further characterise those graphs requiring 1, 2 or 3 edge contractions, respectively, to decrease their semitotal domination number. We then study the complexity of the problem for $k=1$ and obtain in particular a complete complexity dichotomy for monogenic classes.



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