A bipartite graph $G$ such that for any partition $X$ and $Y$, $alpha(G)> max {X,Y}$
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The question is
Construct a bipartite graph $G$ such that for any partition $X$ and $Y$, $alpha(G)> max {X,Y}$. Explain.
I did this graph:

Here it works, $alpha (G) =9$ (marked in blue box), and each partition is $7$. However, if we flip the red circled vertices so that the $3$ top vertices become in $Y$-partition $Y$ will be equal to $9$, which violates what I want to prove. Is there any way to fix my graph?
proof-verification graph-theory
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add a comment |
$begingroup$
The question is
Construct a bipartite graph $G$ such that for any partition $X$ and $Y$, $alpha(G)> max {X,Y}$. Explain.
I did this graph:

Here it works, $alpha (G) =9$ (marked in blue box), and each partition is $7$. However, if we flip the red circled vertices so that the $3$ top vertices become in $Y$-partition $Y$ will be equal to $9$, which violates what I want to prove. Is there any way to fix my graph?
proof-verification graph-theory
$endgroup$
$begingroup$
Can you please tell me what $alpha(G)$ is?
$endgroup$
– user614671
Dec 10 '18 at 18:14
add a comment |
$begingroup$
The question is
Construct a bipartite graph $G$ such that for any partition $X$ and $Y$, $alpha(G)> max {X,Y}$. Explain.
I did this graph:

Here it works, $alpha (G) =9$ (marked in blue box), and each partition is $7$. However, if we flip the red circled vertices so that the $3$ top vertices become in $Y$-partition $Y$ will be equal to $9$, which violates what I want to prove. Is there any way to fix my graph?
proof-verification graph-theory
$endgroup$
The question is
Construct a bipartite graph $G$ such that for any partition $X$ and $Y$, $alpha(G)> max {X,Y}$. Explain.
I did this graph:

Here it works, $alpha (G) =9$ (marked in blue box), and each partition is $7$. However, if we flip the red circled vertices so that the $3$ top vertices become in $Y$-partition $Y$ will be equal to $9$, which violates what I want to prove. Is there any way to fix my graph?
proof-verification graph-theory
proof-verification graph-theory
edited Dec 10 '18 at 13:48
Saad
19.7k92352
19.7k92352
asked Dec 10 '18 at 11:39
Fatmaelzahraa ElsheimyFatmaelzahraa Elsheimy
162
162
$begingroup$
Can you please tell me what $alpha(G)$ is?
$endgroup$
– user614671
Dec 10 '18 at 18:14
add a comment |
$begingroup$
Can you please tell me what $alpha(G)$ is?
$endgroup$
– user614671
Dec 10 '18 at 18:14
$begingroup$
Can you please tell me what $alpha(G)$ is?
$endgroup$
– user614671
Dec 10 '18 at 18:14
$begingroup$
Can you please tell me what $alpha(G)$ is?
$endgroup$
– user614671
Dec 10 '18 at 18:14
add a comment |
1 Answer
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$begingroup$
When you flip the graph then y will have cardinality 9 and maximal independant set will become 9 .
So it proves what you are trying to prove.
$endgroup$
1
$begingroup$
But we want strict greater, not greater or equals.
$endgroup$
– nafhgood
Dec 10 '18 at 16:17
add a comment |
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1 Answer
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1 Answer
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oldest
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$begingroup$
When you flip the graph then y will have cardinality 9 and maximal independant set will become 9 .
So it proves what you are trying to prove.
$endgroup$
1
$begingroup$
But we want strict greater, not greater or equals.
$endgroup$
– nafhgood
Dec 10 '18 at 16:17
add a comment |
$begingroup$
When you flip the graph then y will have cardinality 9 and maximal independant set will become 9 .
So it proves what you are trying to prove.
$endgroup$
1
$begingroup$
But we want strict greater, not greater or equals.
$endgroup$
– nafhgood
Dec 10 '18 at 16:17
add a comment |
$begingroup$
When you flip the graph then y will have cardinality 9 and maximal independant set will become 9 .
So it proves what you are trying to prove.
$endgroup$
When you flip the graph then y will have cardinality 9 and maximal independant set will become 9 .
So it proves what you are trying to prove.
answered Dec 10 '18 at 15:41
Saurabh DangeSaurabh Dange
11
11
1
$begingroup$
But we want strict greater, not greater or equals.
$endgroup$
– nafhgood
Dec 10 '18 at 16:17
add a comment |
1
$begingroup$
But we want strict greater, not greater or equals.
$endgroup$
– nafhgood
Dec 10 '18 at 16:17
1
1
$begingroup$
But we want strict greater, not greater or equals.
$endgroup$
– nafhgood
Dec 10 '18 at 16:17
$begingroup$
But we want strict greater, not greater or equals.
$endgroup$
– nafhgood
Dec 10 '18 at 16:17
add a comment |
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$begingroup$
Can you please tell me what $alpha(G)$ is?
$endgroup$
– user614671
Dec 10 '18 at 18:14