Show that $χ_G(i − 1) = 0$
Can you give me a hint for this exercise about Poset (Partially ordered set)?
Let $χ_G(t)$ be the characteristic polynomial of the graphical
arrangement $A_G$. Suppose that $χ_G(i) = 0$, where $i in
> mathbb{N}$, $i > 1$. Show that $χ_G(i − 1) = 0$
By Enumerative Combinatorics from Stanley, chapter 3.11, I know that
the characteristic polynomial $χ_A(x)$ of the arrangement $A$ is $χ_A(x) = sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$.
And if $V = {v_1, . . . , v_p}$, then define the graphical arrangement $A_G$ to be the arrangement in $R^p$ with hyperplanes $x_i = x_j$, where $v_i$ and $v_j$ are adjacent vertices of $G$. The characteristic polynomial $χ_G(t)$ of the graphical arrangement $A_G$ is also the chromatic polynomial of the graph $G$. The value of $χ_G(t)$ at a positive integer $t$ equals the number of ways to color the vertices of the graph $G$ in $t$ colors so that all neighboring pairs of vertices have different colors.
If we have that $χ_G(i) = 0 Rightarrow χ_A(i)=sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$= 0$
I have to proceeding by backward induction?
order-theory matroids
add a comment |
Can you give me a hint for this exercise about Poset (Partially ordered set)?
Let $χ_G(t)$ be the characteristic polynomial of the graphical
arrangement $A_G$. Suppose that $χ_G(i) = 0$, where $i in
> mathbb{N}$, $i > 1$. Show that $χ_G(i − 1) = 0$
By Enumerative Combinatorics from Stanley, chapter 3.11, I know that
the characteristic polynomial $χ_A(x)$ of the arrangement $A$ is $χ_A(x) = sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$.
And if $V = {v_1, . . . , v_p}$, then define the graphical arrangement $A_G$ to be the arrangement in $R^p$ with hyperplanes $x_i = x_j$, where $v_i$ and $v_j$ are adjacent vertices of $G$. The characteristic polynomial $χ_G(t)$ of the graphical arrangement $A_G$ is also the chromatic polynomial of the graph $G$. The value of $χ_G(t)$ at a positive integer $t$ equals the number of ways to color the vertices of the graph $G$ in $t$ colors so that all neighboring pairs of vertices have different colors.
If we have that $χ_G(i) = 0 Rightarrow χ_A(i)=sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$= 0$
I have to proceeding by backward induction?
order-theory matroids
I don't understand why this was downvoted; on the face of it, it looks like a high quality question.
– Shaun
Nov 26 at 1:25
add a comment |
Can you give me a hint for this exercise about Poset (Partially ordered set)?
Let $χ_G(t)$ be the characteristic polynomial of the graphical
arrangement $A_G$. Suppose that $χ_G(i) = 0$, where $i in
> mathbb{N}$, $i > 1$. Show that $χ_G(i − 1) = 0$
By Enumerative Combinatorics from Stanley, chapter 3.11, I know that
the characteristic polynomial $χ_A(x)$ of the arrangement $A$ is $χ_A(x) = sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$.
And if $V = {v_1, . . . , v_p}$, then define the graphical arrangement $A_G$ to be the arrangement in $R^p$ with hyperplanes $x_i = x_j$, where $v_i$ and $v_j$ are adjacent vertices of $G$. The characteristic polynomial $χ_G(t)$ of the graphical arrangement $A_G$ is also the chromatic polynomial of the graph $G$. The value of $χ_G(t)$ at a positive integer $t$ equals the number of ways to color the vertices of the graph $G$ in $t$ colors so that all neighboring pairs of vertices have different colors.
If we have that $χ_G(i) = 0 Rightarrow χ_A(i)=sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$= 0$
I have to proceeding by backward induction?
order-theory matroids
Can you give me a hint for this exercise about Poset (Partially ordered set)?
Let $χ_G(t)$ be the characteristic polynomial of the graphical
arrangement $A_G$. Suppose that $χ_G(i) = 0$, where $i in
> mathbb{N}$, $i > 1$. Show that $χ_G(i − 1) = 0$
By Enumerative Combinatorics from Stanley, chapter 3.11, I know that
the characteristic polynomial $χ_A(x)$ of the arrangement $A$ is $χ_A(x) = sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$.
And if $V = {v_1, . . . , v_p}$, then define the graphical arrangement $A_G$ to be the arrangement in $R^p$ with hyperplanes $x_i = x_j$, where $v_i$ and $v_j$ are adjacent vertices of $G$. The characteristic polynomial $χ_G(t)$ of the graphical arrangement $A_G$ is also the chromatic polynomial of the graph $G$. The value of $χ_G(t)$ at a positive integer $t$ equals the number of ways to color the vertices of the graph $G$ in $t$ colors so that all neighboring pairs of vertices have different colors.
If we have that $χ_G(i) = 0 Rightarrow χ_A(i)=sum_{t in L(A)} mu(hat0,t)x^{dim(t)}$= 0$
I have to proceeding by backward induction?
order-theory matroids
order-theory matroids
asked Nov 26 at 1:14
Vlllbbb1777
113
113
I don't understand why this was downvoted; on the face of it, it looks like a high quality question.
– Shaun
Nov 26 at 1:25
add a comment |
I don't understand why this was downvoted; on the face of it, it looks like a high quality question.
– Shaun
Nov 26 at 1:25
I don't understand why this was downvoted; on the face of it, it looks like a high quality question.
– Shaun
Nov 26 at 1:25
I don't understand why this was downvoted; on the face of it, it looks like a high quality question.
– Shaun
Nov 26 at 1:25
add a comment |
active
oldest
votes
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3013665%2fshow-that-%25cf%2587-gi-%25e2%2588%2592-1-0%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
active
oldest
votes
active
oldest
votes
active
oldest
votes
active
oldest
votes
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3013665%2fshow-that-%25cf%2587-gi-%25e2%2588%2592-1-0%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
I don't understand why this was downvoted; on the face of it, it looks like a high quality question.
– Shaun
Nov 26 at 1:25