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arXiv · 2402.15669

Solution to an open problem on Laplacian ratio

T. Wu
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Abstract

Let G be a graph. The Laplacian ratio of G is the permanent of the Laplacian matrix of G divided by the product of degrees of all vertices. The computational complexity of Laplacian ratio is #P-complete. Brualdi and Goldwasser studied systematicly the properties of Laplacian ratios of graphs. And they proposed an open problem: what is the minimum value of the Laplacian ratios of trees with n vertices having diameter at least k ? In this paper, we give a solution to the problem.

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T. Wu. 2024-02-24. Solution to an open problem on Laplacian ratio. https://arxiv.org/abs/2402.15669

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