Monochromatic triangle - graph coloring
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I'm trying to find the smallest $n_c$ for which the problem of proving a complete graph with $n$ vertices with edges colored with $c$ colors has a monochromatic triangle could be simplified to a problem of proving the same for a smaller graph of $m_{c-1} < n$ vertices and $c-1$ colors using the Pigeonhole principle. $n$ should be a function of $c$.
This is similar to how the problem of proving that in a graph with 17 vertices where the edges are colored with 3 colors we could find a triangle can be simplified to proving that in a complete graph with 6 vertices and 2 colors there is a monochromatic triangle. Appreciate any help you could provide!
graph-theory pigeonhole-principle coloring ramsey-theory
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add a comment |
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I'm trying to find the smallest $n_c$ for which the problem of proving a complete graph with $n$ vertices with edges colored with $c$ colors has a monochromatic triangle could be simplified to a problem of proving the same for a smaller graph of $m_{c-1} < n$ vertices and $c-1$ colors using the Pigeonhole principle. $n$ should be a function of $c$.
This is similar to how the problem of proving that in a graph with 17 vertices where the edges are colored with 3 colors we could find a triangle can be simplified to proving that in a complete graph with 6 vertices and 2 colors there is a monochromatic triangle. Appreciate any help you could provide!
graph-theory pigeonhole-principle coloring ramsey-theory
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Using such methods stops giving tight bounds quickly. This is confirmed by the partial results on various Ramsey numbers.
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– Zachary Hunter
Jan 6 at 19:22
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my answer at: math.stackexchange.com/questions/935143/… shows all $K_6$ actually have 2 monchromatic triangles in 2 colors, only 3 colorings of higher $K_n$ that force both to break, need be considered.
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– Roddy MacPhee
Mar 7 at 19:45
add a comment |
$begingroup$
I'm trying to find the smallest $n_c$ for which the problem of proving a complete graph with $n$ vertices with edges colored with $c$ colors has a monochromatic triangle could be simplified to a problem of proving the same for a smaller graph of $m_{c-1} < n$ vertices and $c-1$ colors using the Pigeonhole principle. $n$ should be a function of $c$.
This is similar to how the problem of proving that in a graph with 17 vertices where the edges are colored with 3 colors we could find a triangle can be simplified to proving that in a complete graph with 6 vertices and 2 colors there is a monochromatic triangle. Appreciate any help you could provide!
graph-theory pigeonhole-principle coloring ramsey-theory
$endgroup$
I'm trying to find the smallest $n_c$ for which the problem of proving a complete graph with $n$ vertices with edges colored with $c$ colors has a monochromatic triangle could be simplified to a problem of proving the same for a smaller graph of $m_{c-1} < n$ vertices and $c-1$ colors using the Pigeonhole principle. $n$ should be a function of $c$.
This is similar to how the problem of proving that in a graph with 17 vertices where the edges are colored with 3 colors we could find a triangle can be simplified to proving that in a complete graph with 6 vertices and 2 colors there is a monochromatic triangle. Appreciate any help you could provide!
graph-theory pigeonhole-principle coloring ramsey-theory
graph-theory pigeonhole-principle coloring ramsey-theory
edited Jan 6 at 19:27
Matthew Larson
asked Jan 6 at 19:11
Matthew LarsonMatthew Larson
366
366
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Using such methods stops giving tight bounds quickly. This is confirmed by the partial results on various Ramsey numbers.
$endgroup$
– Zachary Hunter
Jan 6 at 19:22
$begingroup$
my answer at: math.stackexchange.com/questions/935143/… shows all $K_6$ actually have 2 monchromatic triangles in 2 colors, only 3 colorings of higher $K_n$ that force both to break, need be considered.
$endgroup$
– Roddy MacPhee
Mar 7 at 19:45
add a comment |
$begingroup$
Using such methods stops giving tight bounds quickly. This is confirmed by the partial results on various Ramsey numbers.
$endgroup$
– Zachary Hunter
Jan 6 at 19:22
$begingroup$
my answer at: math.stackexchange.com/questions/935143/… shows all $K_6$ actually have 2 monchromatic triangles in 2 colors, only 3 colorings of higher $K_n$ that force both to break, need be considered.
$endgroup$
– Roddy MacPhee
Mar 7 at 19:45
$begingroup$
Using such methods stops giving tight bounds quickly. This is confirmed by the partial results on various Ramsey numbers.
$endgroup$
– Zachary Hunter
Jan 6 at 19:22
$begingroup$
Using such methods stops giving tight bounds quickly. This is confirmed by the partial results on various Ramsey numbers.
$endgroup$
– Zachary Hunter
Jan 6 at 19:22
$begingroup$
my answer at: math.stackexchange.com/questions/935143/… shows all $K_6$ actually have 2 monchromatic triangles in 2 colors, only 3 colorings of higher $K_n$ that force both to break, need be considered.
$endgroup$
– Roddy MacPhee
Mar 7 at 19:45
$begingroup$
my answer at: math.stackexchange.com/questions/935143/… shows all $K_6$ actually have 2 monchromatic triangles in 2 colors, only 3 colorings of higher $K_n$ that force both to break, need be considered.
$endgroup$
– Roddy MacPhee
Mar 7 at 19:45
add a comment |
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$begingroup$
Using such methods stops giving tight bounds quickly. This is confirmed by the partial results on various Ramsey numbers.
$endgroup$
– Zachary Hunter
Jan 6 at 19:22
$begingroup$
my answer at: math.stackexchange.com/questions/935143/… shows all $K_6$ actually have 2 monchromatic triangles in 2 colors, only 3 colorings of higher $K_n$ that force both to break, need be considered.
$endgroup$
– Roddy MacPhee
Mar 7 at 19:45