How many ways are there to divide $n$ dancers into dance circles?












0














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.










share|cite|improve this question
























  • 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
















0














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.










share|cite|improve this question
























  • 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














0












0








0







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.










share|cite|improve this question















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






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








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


















  • 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










1 Answer
1






active

oldest

votes


















1














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 $n!$.






share|cite|improve this answer





















    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
    });


    }
    });














    draft saved

    draft discarded


















    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









    1














    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 $n!$.






    share|cite|improve this answer


























      1














      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 $n!$.






      share|cite|improve this answer
























        1












        1








        1






        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 $n!$.






        share|cite|improve this answer












        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 $n!$.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Dec 2 at 11:33









        I like Serena

        3,6921718




        3,6921718






























            draft saved

            draft discarded




















































            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.




            draft saved


            draft discarded














            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





















































            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







            Popular posts from this blog

            Berounka

            Sphinx de Gizeh

            Different font size/position of beamer's navigation symbols template's content depending on regular/plain...