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lower and upper bounds between energy, laplacian energy, and sombor index of some graphs
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نویسنده
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barzegar hasan
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منبع
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iranian journal of mathematical chemistry - 2025 - دوره : 16 - شماره : 1 - صفحه:33 -38
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چکیده
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ivan gutman has introduced two essential indices; the energy of a graph g, and the sombor index of that. $varepsilon(g)$, which stands for the first index, is the sum of the absolute values of all eigenvalues related to the adjacency matrix of the graph $g$. the second, defined as $so(g)=sum _{uv in e(g)}sqrt{d_u^2+d_v^2}$, where $d_u$ and $d_v$ are the degrees of vertices $u$ and $v$ in $g$, respectively. it was proved that if $g$ is a graph of order at least 3, then $varepsilon(g)leq so(g)$ and if $g$ is a connected graph of order $n$ that is not $p_n$ for $nleq 8$, then $varepsilon(g)leq frac{so(g)}{2}$.in this paper, we have strengthened these results and will obtain several lower and upper bounds between the energy of a graph, laplacian energy, and the sombor index.
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کلیدواژه
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energy of a graph ,laplacian energy ,sombor index
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آدرس
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tafresh university, department of mathematics, iran
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پست الکترونیکی
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barzegar@tafreshu.ac.ir
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Authors
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