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Small cycles, generalized prisms and Hamiltonian cycles in the Bubble-sort graph

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 نشر من قبل Alexey Medvedev N.
 تاريخ النشر 2019
  مجال البحث
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The Bubble-sort graph $BS_n,,ngeqslant 2$, is a Cayley graph over the symmetric group $Sym_n$ generated by transpositions from the set ${(1 2), (2 3),ldots, (n-1 n)}$. It is a bipartite graph containing all even cycles of length $ell$, where $4leqslant ellleqslant n!$. We give an explicit combinatorial characterization of all its $4$- and $6$-cycles. Based on this characterization, we define generalized prisms in $BS_n,,ngeqslant 5$, and present a new approach to construct a Hamiltonian cycle based on these generalized prisms.



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