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Independence Equivalence Classes of Paths and Cycles

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 نشر من قبل Jason Brown
 تاريخ النشر 2018
  مجال البحث
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The independence polynomial of a graph is the generating polynomial for the number of independent sets of each size. Two graphs are said to be textit{independence equivalent} if they have equivalent independence polynomials. We extend previous work by showing that independence equivalence class of every odd path has size 1, while the class can contain arbitrarily many graphs for even paths. We also prove that the independence equivalence class of every even cycle consists of two graphs when $nge 2$ except the independence equivalence class of $C_6$ which consists of three graphs. The odd case remains open, although, using irreducibility results from algebra, we were able show that for a prime $p geq 5$ and $nge 1$ the independence equivalence class of $C_{p^n}$ consists of only two graphs.



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