Abstract
The harmonic index \(H\left( G\right) \) of a graph \(G\) is defined as the sum of the weights \(\frac{2}{d_{u}+ d_{v}}\) of all edges \(uv\) in \(G\), where \(d_{u}\) denotes the degree of a vertex \(u\) in \(G\). In this paper, the harmonic indices of polyomino chains are computed. Also, the extremal polyomino chains with respect to harmonic index are determined.
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Deng, H., Balachandran, S., Ayyaswamy, S.K. et al. The Harmonic Indices of Polyomino Chains. Natl. Acad. Sci. Lett. 37, 451–455 (2014). https://doi.org/10.1007/s40009-014-0249-0
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DOI: https://doi.org/10.1007/s40009-014-0249-0