An Inductive Construction for Hamilton Cycles in Kneser Graphs

نویسنده

  • J. Robert Johnson
چکیده

The Kneser graph K(n, r) has as vertices all r-subsets of an n-set with two vertices adjacent if the corresponding subsets are disjoint. It is conjectured that, except for K(5, 2), these graphs are Hamiltonian for all n ≥ 2r +1. In this note we describe an inductive construction which relates Hamiltonicity of K(2r + 2s, r) to Hamiltonicity of K(2r′+s, r′). This shows (among other things) that Hamiltonicity of K(2r+1, r) for all 3 ≤ r ≤ k implies Hamiltonicity of K(2r+2, r) for all r ≤ 2k+1. Applying this result extends the range of values for which Hamiltonicity of K(n, r) is known. Another consequence is that certain families of Kneser graphs (K( 13r, r) for instance) contain infinitely many Hamiltonian graphs.

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عنوان ژورنال:
  • Electr. J. Comb.

دوره 18  شماره 

صفحات  -

تاریخ انتشار 2011