On Hadamard diagonalizable graphs

  title={On Hadamard diagonalizable graphs},
  author={Sasmita Barik and Shaun M. Fallat and Steve Kirkland},
  journal={Linear Algebra and its Applications},
Of interest here is a characterization of the undirected graphs G such that the Laplacian matrix associated with G can be diagonalized by some Hadamard matrix. Many interesting and fundamental properties are presented for such graphs along with a partial characterization of the cographs that have this property. 
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