How to compute the coefficient of a generating function?Convolution of Generating FunctionsWhat is the...

Sundering Titan and basic normal lands and snow lands

Learning to quickly identify valid fingering for piano?

Has a sovereign Communist government ever run, and conceded loss, on a fair election?

Linear Combination of Atomic Orbitals

Is divide-by-zero a security vulnerability?

Area Under the Curve - Variable and Log Transformed Variable

Professor forcing me to attend a conference

If nine coins are tossed, what is the probability that the number of heads is even?

What is the purpose of a disclaimer like "this is not legal advice"?

Deal the cards to the players

Is every open circuit a capacitor?

Computing the volume of a simplex-like object with constraints

What can I do if someone tampers with my SSH public key?

Replacing tantalum capacitor with ceramic capacitor for Op Amps

What does it mean when I add a new variable to my linear model and the R^2 stays the same?

Can a Mexican citizen living in US under DACA drive to Canada?

Why are special aircraft used for the carriers in the United States Navy?

Convert an array of objects to array of the objects' values

ESPP--any reason not to go all in?

Named nets not connected in Eagle board design

Why do we call complex numbers “numbers” but we don’t consider 2 vectors numbers?

Should I use HTTPS on a domain that will only be used for redirection?

Paper published similar to PhD thesis

Is this nominative case or accusative case?



How to compute the coefficient of a generating function?


Convolution of Generating FunctionsWhat is the coefficient of the $x^3$ term in the expansion of $(x^2+x-5)^7$ (See details)?How can I express the multinomial theorem by sum and production for $(a+b+c)$?Generating functions for sequencesSum over subsets of a multisetCoefficient of the generating function $G(z)=frac{1}{1-z-z^2-z^3-z^4}$How to compute the coefficients of this generating functionFinding Probability generating function from moment generating functionWhat is the ordinary generating function of this series?Closed formula of $(1+x_1)(1+x_1+x_2)^2dots(1+x_1+dots+x_n)^n$













0












$begingroup$


I would like to find a closed formula for the coefficients of the generating function
$$f(x)=-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
left( {x}^{2}+1 right) left( x-1 right) ^{3}}} .$$



I am trying to do the following.
begin{align}
f(x)=sum_{i,j,k_1,k_2,k_3=0}^{infty} (-x)^i (-x^2)^j x^{k_1+k_2+k_3}(1+6x-2x^2+6x^3+x^4).
end{align}



The expression is very complicated. Are there some simpler method (or some software) to find a closed formula for the coefficients? Thank you very much.










share|cite|improve this question











$endgroup$








  • 3




    $begingroup$
    Tried partial fractions? $$-{x^4+6x^3-2x^2+6x+1over(x+1)(x^2+1)(x-1)^3}={Aover x+1}+{Bx+Cover x^2+1}+{Dover x-1}+{Eover(x-1)^2}+{Fover(x-1)^3}$$
    $endgroup$
    – Gerry Myerson
    14 hours ago
















0












$begingroup$


I would like to find a closed formula for the coefficients of the generating function
$$f(x)=-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
left( {x}^{2}+1 right) left( x-1 right) ^{3}}} .$$



I am trying to do the following.
begin{align}
f(x)=sum_{i,j,k_1,k_2,k_3=0}^{infty} (-x)^i (-x^2)^j x^{k_1+k_2+k_3}(1+6x-2x^2+6x^3+x^4).
end{align}



The expression is very complicated. Are there some simpler method (or some software) to find a closed formula for the coefficients? Thank you very much.










share|cite|improve this question











$endgroup$








  • 3




    $begingroup$
    Tried partial fractions? $$-{x^4+6x^3-2x^2+6x+1over(x+1)(x^2+1)(x-1)^3}={Aover x+1}+{Bx+Cover x^2+1}+{Dover x-1}+{Eover(x-1)^2}+{Fover(x-1)^3}$$
    $endgroup$
    – Gerry Myerson
    14 hours ago














0












0








0





$begingroup$


I would like to find a closed formula for the coefficients of the generating function
$$f(x)=-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
left( {x}^{2}+1 right) left( x-1 right) ^{3}}} .$$



I am trying to do the following.
begin{align}
f(x)=sum_{i,j,k_1,k_2,k_3=0}^{infty} (-x)^i (-x^2)^j x^{k_1+k_2+k_3}(1+6x-2x^2+6x^3+x^4).
end{align}



The expression is very complicated. Are there some simpler method (or some software) to find a closed formula for the coefficients? Thank you very much.










share|cite|improve this question











$endgroup$




I would like to find a closed formula for the coefficients of the generating function
$$f(x)=-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
left( {x}^{2}+1 right) left( x-1 right) ^{3}}} .$$



I am trying to do the following.
begin{align}
f(x)=sum_{i,j,k_1,k_2,k_3=0}^{infty} (-x)^i (-x^2)^j x^{k_1+k_2+k_3}(1+6x-2x^2+6x^3+x^4).
end{align}



The expression is very complicated. Are there some simpler method (or some software) to find a closed formula for the coefficients? Thank you very much.







combinatorics generating-functions






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited 14 hours ago









Rócherz

2,8562821




2,8562821










asked 14 hours ago









LJRLJR

6,63141849




6,63141849








  • 3




    $begingroup$
    Tried partial fractions? $$-{x^4+6x^3-2x^2+6x+1over(x+1)(x^2+1)(x-1)^3}={Aover x+1}+{Bx+Cover x^2+1}+{Dover x-1}+{Eover(x-1)^2}+{Fover(x-1)^3}$$
    $endgroup$
    – Gerry Myerson
    14 hours ago














  • 3




    $begingroup$
    Tried partial fractions? $$-{x^4+6x^3-2x^2+6x+1over(x+1)(x^2+1)(x-1)^3}={Aover x+1}+{Bx+Cover x^2+1}+{Dover x-1}+{Eover(x-1)^2}+{Fover(x-1)^3}$$
    $endgroup$
    – Gerry Myerson
    14 hours ago








3




3




$begingroup$
Tried partial fractions? $$-{x^4+6x^3-2x^2+6x+1over(x+1)(x^2+1)(x-1)^3}={Aover x+1}+{Bx+Cover x^2+1}+{Dover x-1}+{Eover(x-1)^2}+{Fover(x-1)^3}$$
$endgroup$
– Gerry Myerson
14 hours ago




$begingroup$
Tried partial fractions? $$-{x^4+6x^3-2x^2+6x+1over(x+1)(x^2+1)(x-1)^3}={Aover x+1}+{Bx+Cover x^2+1}+{Dover x-1}+{Eover(x-1)^2}+{Fover(x-1)^3}$$
$endgroup$
– Gerry Myerson
14 hours ago










1 Answer
1






active

oldest

votes


















2












$begingroup$

$$-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
left( {x}^{2}+1 right) left( x-1 right) ^{3}}} =frac{0.25}{1-x}-frac{0.75}{1+x}+frac{x}{1+x^2}-frac{1.5}{(1-x)^2}+frac{3}{(1-x)^3}$$

then use the following series and differentiate it two times to replace all terms to series
$$frac{1}{1-x}=sum_{n=0}^{infty}x^n$$






share|cite|improve this answer









$endgroup$













    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%2f3138773%2fhow-to-compute-the-coefficient-of-a-generating-function%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









    2












    $begingroup$

    $$-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
    left( {x}^{2}+1 right) left( x-1 right) ^{3}}} =frac{0.25}{1-x}-frac{0.75}{1+x}+frac{x}{1+x^2}-frac{1.5}{(1-x)^2}+frac{3}{(1-x)^3}$$

    then use the following series and differentiate it two times to replace all terms to series
    $$frac{1}{1-x}=sum_{n=0}^{infty}x^n$$






    share|cite|improve this answer









    $endgroup$


















      2












      $begingroup$

      $$-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
      left( {x}^{2}+1 right) left( x-1 right) ^{3}}} =frac{0.25}{1-x}-frac{0.75}{1+x}+frac{x}{1+x^2}-frac{1.5}{(1-x)^2}+frac{3}{(1-x)^3}$$

      then use the following series and differentiate it two times to replace all terms to series
      $$frac{1}{1-x}=sum_{n=0}^{infty}x^n$$






      share|cite|improve this answer









      $endgroup$
















        2












        2








        2





        $begingroup$

        $$-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
        left( {x}^{2}+1 right) left( x-1 right) ^{3}}} =frac{0.25}{1-x}-frac{0.75}{1+x}+frac{x}{1+x^2}-frac{1.5}{(1-x)^2}+frac{3}{(1-x)^3}$$

        then use the following series and differentiate it two times to replace all terms to series
        $$frac{1}{1-x}=sum_{n=0}^{infty}x^n$$






        share|cite|improve this answer









        $endgroup$



        $$-{frac {{x}^{4}+6,{x}^{3}-2,{x}^{2}+6,x+1}{ left( x+1 right)
        left( {x}^{2}+1 right) left( x-1 right) ^{3}}} =frac{0.25}{1-x}-frac{0.75}{1+x}+frac{x}{1+x^2}-frac{1.5}{(1-x)^2}+frac{3}{(1-x)^3}$$

        then use the following series and differentiate it two times to replace all terms to series
        $$frac{1}{1-x}=sum_{n=0}^{infty}x^n$$







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered 14 hours ago









        E.H.EE.H.E

        15.8k11968




        15.8k11968






























            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.




            draft saved


            draft discarded














            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3138773%2fhow-to-compute-the-coefficient-of-a-generating-function%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

            Nidaros erkebispedøme

            Birsay

            Was Woodrow Wilson really a Liberal?Was World War I a war of liberals against authoritarians?Founding Fathers...