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Corrected the definition of $z_{i,j}$.
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Combinatorial graph optimization problem on integer adjacency matrices

We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$$z_{i,j}:=\frac{M_{i,j}}{M_{i,j}+\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges).

Combinatorial optimization problem on integer matrices

We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges).

Combinatorial graph optimization problem on integer adjacency matrices

We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{M_{i,j}+\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges).

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We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges). Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network.

We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges). Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network.

We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges).

Added note about graph-theory perspective
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We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges). Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network.

We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?

We are given a $n\times n$ symmetric matrix $M$ whose entries are positive integers.

Let $z_{i,j}:=\frac{M_{i,j}}{\sum_{k\neq i,j}\min(M_{i,k},M_{k,j})}$ for all $1\le i<j \le n$, and $z:=\sum_{i<j}z_{i,j}$.


Question: Can we prove that the maximum value $z^*$ of $z$ over all matrices $M$ defined above is upper bounded by $\alpha n$ for some absolute constant $\alpha$?



Note: $M$ can be viewed as the adjacency matrix of a given undirected multi-edge graph. For all $1\le i<j\le n$, $z_{i,j}$ can be viewed as a function of the amount of "flow" between the two nodes $i$ and $j$ passing through paths of length at most $2$ (i.e., containing $2$ edges). Alternatively, for all $1\le i<j\le n$, $M_{i,j}$ can be viewed as an integer capacity in a symmetric flow network.

Added the tag "Graph-theory" because matrices $M$ can be viewed as adjacency matrices, and $z_{i,j}$ can be viewed as a kind of flow in the given network.
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