Strengthening Bertrand's postulate using the prime number theorem












0












$begingroup$


In its page on Bertrand's postulate Wikipedia says




It follows from the prime number theorem that for any real
$varepsilon >0$ there is an $n_0 > 0$ such that for all $n > n_0$
there is a prime $p $ such that $n < p < ( 1 + ε )n$ .




I need to quote this result for $varepsilon = 1/2$. I'd like a reference more formal than Wikipedia.










share|cite|improve this question











$endgroup$








  • 1




    $begingroup$
    Why don't you cite the reference that very source that Wikipedia used: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.
    $endgroup$
    – fleablood
    Jul 16 '18 at 0:00










  • $begingroup$
    @fleablood Of course. I missed that reference. Post as an answer, or I can delete the question as too narrow.
    $endgroup$
    – Ethan Bolker
    Jul 16 '18 at 0:04










  • $begingroup$
    I think it better to close-as-duplicate, see How far to nearest/next prime? where the answers gives some formal references.
    $endgroup$
    – hardmath
    Jan 2 at 18:22










  • $begingroup$
    Possible duplicate of How far to nearest/next prime?
    $endgroup$
    – hardmath
    Jan 2 at 18:23
















0












$begingroup$


In its page on Bertrand's postulate Wikipedia says




It follows from the prime number theorem that for any real
$varepsilon >0$ there is an $n_0 > 0$ such that for all $n > n_0$
there is a prime $p $ such that $n < p < ( 1 + ε )n$ .




I need to quote this result for $varepsilon = 1/2$. I'd like a reference more formal than Wikipedia.










share|cite|improve this question











$endgroup$








  • 1




    $begingroup$
    Why don't you cite the reference that very source that Wikipedia used: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.
    $endgroup$
    – fleablood
    Jul 16 '18 at 0:00










  • $begingroup$
    @fleablood Of course. I missed that reference. Post as an answer, or I can delete the question as too narrow.
    $endgroup$
    – Ethan Bolker
    Jul 16 '18 at 0:04










  • $begingroup$
    I think it better to close-as-duplicate, see How far to nearest/next prime? where the answers gives some formal references.
    $endgroup$
    – hardmath
    Jan 2 at 18:22










  • $begingroup$
    Possible duplicate of How far to nearest/next prime?
    $endgroup$
    – hardmath
    Jan 2 at 18:23














0












0








0





$begingroup$


In its page on Bertrand's postulate Wikipedia says




It follows from the prime number theorem that for any real
$varepsilon >0$ there is an $n_0 > 0$ such that for all $n > n_0$
there is a prime $p $ such that $n < p < ( 1 + ε )n$ .




I need to quote this result for $varepsilon = 1/2$. I'd like a reference more formal than Wikipedia.










share|cite|improve this question











$endgroup$




In its page on Bertrand's postulate Wikipedia says




It follows from the prime number theorem that for any real
$varepsilon >0$ there is an $n_0 > 0$ such that for all $n > n_0$
there is a prime $p $ such that $n < p < ( 1 + ε )n$ .




I need to quote this result for $varepsilon = 1/2$. I'd like a reference more formal than Wikipedia.







reference-request analytic-number-theory






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Jan 2 at 18:23









hardmath

28.8k95296




28.8k95296










asked Jul 15 '18 at 23:54









Ethan BolkerEthan Bolker

42.1k548111




42.1k548111








  • 1




    $begingroup$
    Why don't you cite the reference that very source that Wikipedia used: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.
    $endgroup$
    – fleablood
    Jul 16 '18 at 0:00










  • $begingroup$
    @fleablood Of course. I missed that reference. Post as an answer, or I can delete the question as too narrow.
    $endgroup$
    – Ethan Bolker
    Jul 16 '18 at 0:04










  • $begingroup$
    I think it better to close-as-duplicate, see How far to nearest/next prime? where the answers gives some formal references.
    $endgroup$
    – hardmath
    Jan 2 at 18:22










  • $begingroup$
    Possible duplicate of How far to nearest/next prime?
    $endgroup$
    – hardmath
    Jan 2 at 18:23














  • 1




    $begingroup$
    Why don't you cite the reference that very source that Wikipedia used: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.
    $endgroup$
    – fleablood
    Jul 16 '18 at 0:00










  • $begingroup$
    @fleablood Of course. I missed that reference. Post as an answer, or I can delete the question as too narrow.
    $endgroup$
    – Ethan Bolker
    Jul 16 '18 at 0:04










  • $begingroup$
    I think it better to close-as-duplicate, see How far to nearest/next prime? where the answers gives some formal references.
    $endgroup$
    – hardmath
    Jan 2 at 18:22










  • $begingroup$
    Possible duplicate of How far to nearest/next prime?
    $endgroup$
    – hardmath
    Jan 2 at 18:23








1




1




$begingroup$
Why don't you cite the reference that very source that Wikipedia used: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.
$endgroup$
– fleablood
Jul 16 '18 at 0:00




$begingroup$
Why don't you cite the reference that very source that Wikipedia used: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.
$endgroup$
– fleablood
Jul 16 '18 at 0:00












$begingroup$
@fleablood Of course. I missed that reference. Post as an answer, or I can delete the question as too narrow.
$endgroup$
– Ethan Bolker
Jul 16 '18 at 0:04




$begingroup$
@fleablood Of course. I missed that reference. Post as an answer, or I can delete the question as too narrow.
$endgroup$
– Ethan Bolker
Jul 16 '18 at 0:04












$begingroup$
I think it better to close-as-duplicate, see How far to nearest/next prime? where the answers gives some formal references.
$endgroup$
– hardmath
Jan 2 at 18:22




$begingroup$
I think it better to close-as-duplicate, see How far to nearest/next prime? where the answers gives some formal references.
$endgroup$
– hardmath
Jan 2 at 18:22












$begingroup$
Possible duplicate of How far to nearest/next prime?
$endgroup$
– hardmath
Jan 2 at 18:23




$begingroup$
Possible duplicate of How far to nearest/next prime?
$endgroup$
– hardmath
Jan 2 at 18:23










2 Answers
2






active

oldest

votes


















3












$begingroup$

The ariticle on wikipededia cites that with a foot note (as of the time I write this) #8 refering to: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.




from Wikipedia



It follows from the prime number theorem that for any real $ {displaystyle varepsilon >0}$ there is a ${displaystyle n_{0}>0} $ such that for all ${displaystyle n>n_{0}} $ there is a prime $ {displaystyle p}$ such ${displaystyle n<p<(1+varepsilon )n}$. It can be shown, for instance,
that



${displaystyle lim _{nto infty }{frac {pi ((1+varepsilon )n)-pi
> (n)}{n/log n}}=varepsilon ,} $[8]



[8]G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.







share|cite|improve this answer











$endgroup$













  • $begingroup$
    This is pretty unreadable. I doubt that Hardy and Wright says “for any real $epsilon > 0 > epsilon > 0epsilon > 0$, for example (and it doesn’t get better). Can you edit the quote so it doesn’t look like a copy/paste from some non-LaTeX source? Even an image of the relevant Hardy and Wright page would be better than this.
    $endgroup$
    – Steve Kass
    Jul 16 '18 at 0:34












  • $begingroup$
    It is a copy and paste from a non-LaTeX source! I thought the was clear from context.
    $endgroup$
    – fleablood
    Jul 16 '18 at 2:19



















2












$begingroup$

tersely worded, but Dusart gives, for $x geq 396738,$ a prime between $x$ and
$$ x left( 1 + frac{1}{25 log^2 x} right) $$



I think it was on the arxiv, let me find it.



Yes, this is Proposition 6.8.



For your fixed target $3x/2,$ you may fill in the smaller numbers with the table of maximal prime gaps at https://en.wikipedia.org/wiki/Prime_gap#Numerical_results . I went through the thing once by machine, for $p geq 11$ and $p < 4 cdot 10^{18},$ we get gap $g < log^2 p.$






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%2f2852944%2fstrengthening-bertrands-postulate-using-the-prime-number-theorem%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    2 Answers
    2






    active

    oldest

    votes








    2 Answers
    2






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    3












    $begingroup$

    The ariticle on wikipededia cites that with a foot note (as of the time I write this) #8 refering to: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.




    from Wikipedia



    It follows from the prime number theorem that for any real $ {displaystyle varepsilon >0}$ there is a ${displaystyle n_{0}>0} $ such that for all ${displaystyle n>n_{0}} $ there is a prime $ {displaystyle p}$ such ${displaystyle n<p<(1+varepsilon )n}$. It can be shown, for instance,
    that



    ${displaystyle lim _{nto infty }{frac {pi ((1+varepsilon )n)-pi
    > (n)}{n/log n}}=varepsilon ,} $[8]



    [8]G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.







    share|cite|improve this answer











    $endgroup$













    • $begingroup$
      This is pretty unreadable. I doubt that Hardy and Wright says “for any real $epsilon > 0 > epsilon > 0epsilon > 0$, for example (and it doesn’t get better). Can you edit the quote so it doesn’t look like a copy/paste from some non-LaTeX source? Even an image of the relevant Hardy and Wright page would be better than this.
      $endgroup$
      – Steve Kass
      Jul 16 '18 at 0:34












    • $begingroup$
      It is a copy and paste from a non-LaTeX source! I thought the was clear from context.
      $endgroup$
      – fleablood
      Jul 16 '18 at 2:19
















    3












    $begingroup$

    The ariticle on wikipededia cites that with a foot note (as of the time I write this) #8 refering to: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.




    from Wikipedia



    It follows from the prime number theorem that for any real $ {displaystyle varepsilon >0}$ there is a ${displaystyle n_{0}>0} $ such that for all ${displaystyle n>n_{0}} $ there is a prime $ {displaystyle p}$ such ${displaystyle n<p<(1+varepsilon )n}$. It can be shown, for instance,
    that



    ${displaystyle lim _{nto infty }{frac {pi ((1+varepsilon )n)-pi
    > (n)}{n/log n}}=varepsilon ,} $[8]



    [8]G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.







    share|cite|improve this answer











    $endgroup$













    • $begingroup$
      This is pretty unreadable. I doubt that Hardy and Wright says “for any real $epsilon > 0 > epsilon > 0epsilon > 0$, for example (and it doesn’t get better). Can you edit the quote so it doesn’t look like a copy/paste from some non-LaTeX source? Even an image of the relevant Hardy and Wright page would be better than this.
      $endgroup$
      – Steve Kass
      Jul 16 '18 at 0:34












    • $begingroup$
      It is a copy and paste from a non-LaTeX source! I thought the was clear from context.
      $endgroup$
      – fleablood
      Jul 16 '18 at 2:19














    3












    3








    3





    $begingroup$

    The ariticle on wikipededia cites that with a foot note (as of the time I write this) #8 refering to: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.




    from Wikipedia



    It follows from the prime number theorem that for any real $ {displaystyle varepsilon >0}$ there is a ${displaystyle n_{0}>0} $ such that for all ${displaystyle n>n_{0}} $ there is a prime $ {displaystyle p}$ such ${displaystyle n<p<(1+varepsilon )n}$. It can be shown, for instance,
    that



    ${displaystyle lim _{nto infty }{frac {pi ((1+varepsilon )n)-pi
    > (n)}{n/log n}}=varepsilon ,} $[8]



    [8]G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.







    share|cite|improve this answer











    $endgroup$



    The ariticle on wikipededia cites that with a foot note (as of the time I write this) #8 refering to: G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.




    from Wikipedia



    It follows from the prime number theorem that for any real $ {displaystyle varepsilon >0}$ there is a ${displaystyle n_{0}>0} $ such that for all ${displaystyle n>n_{0}} $ there is a prime $ {displaystyle p}$ such ${displaystyle n<p<(1+varepsilon )n}$. It can be shown, for instance,
    that



    ${displaystyle lim _{nto infty }{frac {pi ((1+varepsilon )n)-pi
    > (n)}{n/log n}}=varepsilon ,} $[8]



    [8]G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 6th ed., Oxford University Press, 2008, p. 494.








    share|cite|improve this answer














    share|cite|improve this answer



    share|cite|improve this answer








    edited Jul 16 '18 at 2:28

























    answered Jul 16 '18 at 0:12









    fleabloodfleablood

    68.7k22685




    68.7k22685












    • $begingroup$
      This is pretty unreadable. I doubt that Hardy and Wright says “for any real $epsilon > 0 > epsilon > 0epsilon > 0$, for example (and it doesn’t get better). Can you edit the quote so it doesn’t look like a copy/paste from some non-LaTeX source? Even an image of the relevant Hardy and Wright page would be better than this.
      $endgroup$
      – Steve Kass
      Jul 16 '18 at 0:34












    • $begingroup$
      It is a copy and paste from a non-LaTeX source! I thought the was clear from context.
      $endgroup$
      – fleablood
      Jul 16 '18 at 2:19


















    • $begingroup$
      This is pretty unreadable. I doubt that Hardy and Wright says “for any real $epsilon > 0 > epsilon > 0epsilon > 0$, for example (and it doesn’t get better). Can you edit the quote so it doesn’t look like a copy/paste from some non-LaTeX source? Even an image of the relevant Hardy and Wright page would be better than this.
      $endgroup$
      – Steve Kass
      Jul 16 '18 at 0:34












    • $begingroup$
      It is a copy and paste from a non-LaTeX source! I thought the was clear from context.
      $endgroup$
      – fleablood
      Jul 16 '18 at 2:19
















    $begingroup$
    This is pretty unreadable. I doubt that Hardy and Wright says “for any real $epsilon > 0 > epsilon > 0epsilon > 0$, for example (and it doesn’t get better). Can you edit the quote so it doesn’t look like a copy/paste from some non-LaTeX source? Even an image of the relevant Hardy and Wright page would be better than this.
    $endgroup$
    – Steve Kass
    Jul 16 '18 at 0:34






    $begingroup$
    This is pretty unreadable. I doubt that Hardy and Wright says “for any real $epsilon > 0 > epsilon > 0epsilon > 0$, for example (and it doesn’t get better). Can you edit the quote so it doesn’t look like a copy/paste from some non-LaTeX source? Even an image of the relevant Hardy and Wright page would be better than this.
    $endgroup$
    – Steve Kass
    Jul 16 '18 at 0:34














    $begingroup$
    It is a copy and paste from a non-LaTeX source! I thought the was clear from context.
    $endgroup$
    – fleablood
    Jul 16 '18 at 2:19




    $begingroup$
    It is a copy and paste from a non-LaTeX source! I thought the was clear from context.
    $endgroup$
    – fleablood
    Jul 16 '18 at 2:19











    2












    $begingroup$

    tersely worded, but Dusart gives, for $x geq 396738,$ a prime between $x$ and
    $$ x left( 1 + frac{1}{25 log^2 x} right) $$



    I think it was on the arxiv, let me find it.



    Yes, this is Proposition 6.8.



    For your fixed target $3x/2,$ you may fill in the smaller numbers with the table of maximal prime gaps at https://en.wikipedia.org/wiki/Prime_gap#Numerical_results . I went through the thing once by machine, for $p geq 11$ and $p < 4 cdot 10^{18},$ we get gap $g < log^2 p.$






    share|cite|improve this answer











    $endgroup$


















      2












      $begingroup$

      tersely worded, but Dusart gives, for $x geq 396738,$ a prime between $x$ and
      $$ x left( 1 + frac{1}{25 log^2 x} right) $$



      I think it was on the arxiv, let me find it.



      Yes, this is Proposition 6.8.



      For your fixed target $3x/2,$ you may fill in the smaller numbers with the table of maximal prime gaps at https://en.wikipedia.org/wiki/Prime_gap#Numerical_results . I went through the thing once by machine, for $p geq 11$ and $p < 4 cdot 10^{18},$ we get gap $g < log^2 p.$






      share|cite|improve this answer











      $endgroup$
















        2












        2








        2





        $begingroup$

        tersely worded, but Dusart gives, for $x geq 396738,$ a prime between $x$ and
        $$ x left( 1 + frac{1}{25 log^2 x} right) $$



        I think it was on the arxiv, let me find it.



        Yes, this is Proposition 6.8.



        For your fixed target $3x/2,$ you may fill in the smaller numbers with the table of maximal prime gaps at https://en.wikipedia.org/wiki/Prime_gap#Numerical_results . I went through the thing once by machine, for $p geq 11$ and $p < 4 cdot 10^{18},$ we get gap $g < log^2 p.$






        share|cite|improve this answer











        $endgroup$



        tersely worded, but Dusart gives, for $x geq 396738,$ a prime between $x$ and
        $$ x left( 1 + frac{1}{25 log^2 x} right) $$



        I think it was on the arxiv, let me find it.



        Yes, this is Proposition 6.8.



        For your fixed target $3x/2,$ you may fill in the smaller numbers with the table of maximal prime gaps at https://en.wikipedia.org/wiki/Prime_gap#Numerical_results . I went through the thing once by machine, for $p geq 11$ and $p < 4 cdot 10^{18},$ we get gap $g < log^2 p.$







        share|cite|improve this answer














        share|cite|improve this answer



        share|cite|improve this answer








        edited Jul 16 '18 at 0:38

























        answered Jul 16 '18 at 0:22









        Will JagyWill Jagy

        102k5101199




        102k5101199






























            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%2f2852944%2fstrengthening-bertrands-postulate-using-the-prime-number-theorem%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

            MongoDB - Not Authorized To Execute Command

            How to fix TextFormField cause rebuild widget in Flutter

            in spring boot 2.1 many test slices are not allowed anymore due to multiple @BootstrapWith