How many ways are there to divide $n$ dancers into dance circles?
We have $n$ dancers, and they need to dance in circles. The order of the dancers inside each circle does matter. The circles themselves aren't ordered.
In the original question there was an additional requirement that the size of each dance circle is at least $2$, but I think that part can be completed later using the Inclusion–exclusion principle.
combinatorics
add a comment |
We have $n$ dancers, and they need to dance in circles. The order of the dancers inside each circle does matter. The circles themselves aren't ordered.
In the original question there was an additional requirement that the size of each dance circle is at least $2$, but I think that part can be completed later using the Inclusion–exclusion principle.
combinatorics
Have you calculated the answer for small values of $n$?
– Gerry Myerson
Dec 2 at 11:33
I haven't, but since the answer turned out to be so simple, I assume that would have helped my figure it out. Though if I would have tried small n, I would have included the second restriction, which makes the formula more complex.
– Amit Levy
Dec 3 at 6:57
add a comment |
We have $n$ dancers, and they need to dance in circles. The order of the dancers inside each circle does matter. The circles themselves aren't ordered.
In the original question there was an additional requirement that the size of each dance circle is at least $2$, but I think that part can be completed later using the Inclusion–exclusion principle.
combinatorics
We have $n$ dancers, and they need to dance in circles. The order of the dancers inside each circle does matter. The circles themselves aren't ordered.
In the original question there was an additional requirement that the size of each dance circle is at least $2$, but I think that part can be completed later using the Inclusion–exclusion principle.
combinatorics
combinatorics
edited Dec 2 at 11:10
Henrik
5,95692030
5,95692030
asked Dec 2 at 11:08
Amit Levy
232
232
Have you calculated the answer for small values of $n$?
– Gerry Myerson
Dec 2 at 11:33
I haven't, but since the answer turned out to be so simple, I assume that would have helped my figure it out. Though if I would have tried small n, I would have included the second restriction, which makes the formula more complex.
– Amit Levy
Dec 3 at 6:57
add a comment |
Have you calculated the answer for small values of $n$?
– Gerry Myerson
Dec 2 at 11:33
I haven't, but since the answer turned out to be so simple, I assume that would have helped my figure it out. Though if I would have tried small n, I would have included the second restriction, which makes the formula more complex.
– Amit Levy
Dec 3 at 6:57
Have you calculated the answer for small values of $n$?
– Gerry Myerson
Dec 2 at 11:33
Have you calculated the answer for small values of $n$?
– Gerry Myerson
Dec 2 at 11:33
I haven't, but since the answer turned out to be so simple, I assume that would have helped my figure it out. Though if I would have tried small n, I would have included the second restriction, which makes the formula more complex.
– Amit Levy
Dec 3 at 6:57
I haven't, but since the answer turned out to be so simple, I assume that would have helped my figure it out. Though if I would have tried small n, I would have included the second restriction, which makes the formula more complex.
– Amit Levy
Dec 3 at 6:57
add a comment |
1 Answer
1
active
oldest
votes
Suppose we have 3 dancers, then the possible divisions are:
$$S_3={ (1)(2)(3), (1)(23), (2)(13), (3)(12), (123), (132)}$$
The set $S_n$ is the set of permutations of $n$ elements. The permutations are written in cycle notation. Each cycle happens to correspond exactly with a circle of dancers.
In other words, the number of divisions of $n$ dancers is the number of elements in $S_n$, which is $n!$.
add a comment |
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%2f3022502%2fhow-many-ways-are-there-to-divide-n-dancers-into-dance-circles%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Suppose we have 3 dancers, then the possible divisions are:
$$S_3={ (1)(2)(3), (1)(23), (2)(13), (3)(12), (123), (132)}$$
The set $S_n$ is the set of permutations of $n$ elements. The permutations are written in cycle notation. Each cycle happens to correspond exactly with a circle of dancers.
In other words, the number of divisions of $n$ dancers is the number of elements in $S_n$, which is $n!$.
add a comment |
Suppose we have 3 dancers, then the possible divisions are:
$$S_3={ (1)(2)(3), (1)(23), (2)(13), (3)(12), (123), (132)}$$
The set $S_n$ is the set of permutations of $n$ elements. The permutations are written in cycle notation. Each cycle happens to correspond exactly with a circle of dancers.
In other words, the number of divisions of $n$ dancers is the number of elements in $S_n$, which is $n!$.
add a comment |
Suppose we have 3 dancers, then the possible divisions are:
$$S_3={ (1)(2)(3), (1)(23), (2)(13), (3)(12), (123), (132)}$$
The set $S_n$ is the set of permutations of $n$ elements. The permutations are written in cycle notation. Each cycle happens to correspond exactly with a circle of dancers.
In other words, the number of divisions of $n$ dancers is the number of elements in $S_n$, which is $n!$.
Suppose we have 3 dancers, then the possible divisions are:
$$S_3={ (1)(2)(3), (1)(23), (2)(13), (3)(12), (123), (132)}$$
The set $S_n$ is the set of permutations of $n$ elements. The permutations are written in cycle notation. Each cycle happens to correspond exactly with a circle of dancers.
In other words, the number of divisions of $n$ dancers is the number of elements in $S_n$, which is $n!$.
answered Dec 2 at 11:33
I like Serena
3,6921718
3,6921718
add a comment |
add a comment |
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%2f3022502%2fhow-many-ways-are-there-to-divide-n-dancers-into-dance-circles%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
Have you calculated the answer for small values of $n$?
– Gerry Myerson
Dec 2 at 11:33
I haven't, but since the answer turned out to be so simple, I assume that would have helped my figure it out. Though if I would have tried small n, I would have included the second restriction, which makes the formula more complex.
– Amit Levy
Dec 3 at 6:57