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                * Princeton Discrete Math Seminar *
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Speaker: Alexey Pokrovskiy (UCL)

TODAY, Tuesday April 22, 3:00 in Fine Hall 224.



Title: Group-harmonious labelings of trees

Consider an order n abelian group G and a tree T on n vertices.
When is it possible to (bijectively) label V(T) by G do that along all
edges xy, the sums x+y are distinct? There are various motivations for
studying this question, such as the Harmonious Labelling Conjecture of
Graham-Sloane, which asks something related for cyclic G. This talk will
be about giving a necessary and sufficient condition for the labelling to
be possible in the case of arbitrary G and large, bounded degree T.
Joint work with Alp Müyesser.


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