Complete graphs with zero diagonal inverse

Alexander Farrugia, John Baptist Gauci, Irene Sciriha


If the inverse of a non-singular real symmetric matrix that represents an edge-weighted graph with no loops has zero diagonal, then the inverse itself is the matrix of a loopless graph. Here we show that such graphs having non--zero weight on each edge always exist if their number of vertices is at least 6.


NSSD, G-nutful graph, circulant matrix, complete graph.

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ISSN: 1855-3974

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