Recursive square root inside square root problem

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I have been debating this issue for days:



I can't find a recursive function of this equation:



$largesqrt2+pi sqrt3+pisqrt4+pisqrt5+dotsb$



has been trying to find a solution this for days now, is what I have achieved so far:



$f(n)=sqrt2 f(n-1), f(1)=sqrt2$



Unfortunately, I do not know how to move forward,
thanks a lot!










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    up vote
    3
    down vote

    favorite
    3












    I have been debating this issue for days:



    I can't find a recursive function of this equation:



    $largesqrt2+pi sqrt3+pisqrt4+pisqrt5+dotsb$



    has been trying to find a solution this for days now, is what I have achieved so far:



    $f(n)=sqrt2 f(n-1), f(1)=sqrt2$



    Unfortunately, I do not know how to move forward,
    thanks a lot!










    share|cite|improve this question























      up vote
      3
      down vote

      favorite
      3









      up vote
      3
      down vote

      favorite
      3






      3





      I have been debating this issue for days:



      I can't find a recursive function of this equation:



      $largesqrt2+pi sqrt3+pisqrt4+pisqrt5+dotsb$



      has been trying to find a solution this for days now, is what I have achieved so far:



      $f(n)=sqrt2 f(n-1), f(1)=sqrt2$



      Unfortunately, I do not know how to move forward,
      thanks a lot!










      share|cite|improve this question













      I have been debating this issue for days:



      I can't find a recursive function of this equation:



      $largesqrt2+pi sqrt3+pisqrt4+pisqrt5+dotsb$



      has been trying to find a solution this for days now, is what I have achieved so far:



      $f(n)=sqrt2 f(n-1), f(1)=sqrt2$



      Unfortunately, I do not know how to move forward,
      thanks a lot!







      sequences-and-series recurrence-relations recursion nested-radicals






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      asked Sep 3 at 7:51









      Gionata Donati

      162




      162




















          1 Answer
          1






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          I would write it as
          $$
          fleft(nright)=sqrtn+1+pi fleft(n+1right),
          $$
          Hence
          $$
          fleft(1right)=sqrt2+pi fleft(2right), fleft(2right)=sqrt3+pi fleft(3right) Rightarrow fleft(1right)=sqrt2+pisqrt3+fleft(3right)
          $$
          which means you search for $fleft(1right)$.
          $$
          fleft(n+1right)=frac1pileft(fleft(nright)^2-n-1right)
          $$






          share|cite|improve this answer




















          • I dont think so, wolfram interprets it as f(0)=0
            – Atmos
            Sep 3 at 9:51










          • I don t think so. However do you want to find a value to this ?
            – Atmos
            Sep 3 at 15:21










          • There is no value for n=0 the sequence i wrote us for n>=1
            – Atmos
            Sep 3 at 15:30






          • 1




            Hi, thank you for your reply. It is not correct, both in Matlab and WolframAlpha the sequence is not correct. link If someone can understand how to correct your formula would be perfect, yesterday I tried but I failed
            – Gionata Donati
            Sep 4 at 8:38











          Your Answer




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          1 Answer
          1






          active

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          1 Answer
          1






          active

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          active

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          up vote
          1
          down vote













          I would write it as
          $$
          fleft(nright)=sqrtn+1+pi fleft(n+1right),
          $$
          Hence
          $$
          fleft(1right)=sqrt2+pi fleft(2right), fleft(2right)=sqrt3+pi fleft(3right) Rightarrow fleft(1right)=sqrt2+pisqrt3+fleft(3right)
          $$
          which means you search for $fleft(1right)$.
          $$
          fleft(n+1right)=frac1pileft(fleft(nright)^2-n-1right)
          $$






          share|cite|improve this answer




















          • I dont think so, wolfram interprets it as f(0)=0
            – Atmos
            Sep 3 at 9:51










          • I don t think so. However do you want to find a value to this ?
            – Atmos
            Sep 3 at 15:21










          • There is no value for n=0 the sequence i wrote us for n>=1
            – Atmos
            Sep 3 at 15:30






          • 1




            Hi, thank you for your reply. It is not correct, both in Matlab and WolframAlpha the sequence is not correct. link If someone can understand how to correct your formula would be perfect, yesterday I tried but I failed
            – Gionata Donati
            Sep 4 at 8:38















          up vote
          1
          down vote













          I would write it as
          $$
          fleft(nright)=sqrtn+1+pi fleft(n+1right),
          $$
          Hence
          $$
          fleft(1right)=sqrt2+pi fleft(2right), fleft(2right)=sqrt3+pi fleft(3right) Rightarrow fleft(1right)=sqrt2+pisqrt3+fleft(3right)
          $$
          which means you search for $fleft(1right)$.
          $$
          fleft(n+1right)=frac1pileft(fleft(nright)^2-n-1right)
          $$






          share|cite|improve this answer




















          • I dont think so, wolfram interprets it as f(0)=0
            – Atmos
            Sep 3 at 9:51










          • I don t think so. However do you want to find a value to this ?
            – Atmos
            Sep 3 at 15:21










          • There is no value for n=0 the sequence i wrote us for n>=1
            – Atmos
            Sep 3 at 15:30






          • 1




            Hi, thank you for your reply. It is not correct, both in Matlab and WolframAlpha the sequence is not correct. link If someone can understand how to correct your formula would be perfect, yesterday I tried but I failed
            – Gionata Donati
            Sep 4 at 8:38













          up vote
          1
          down vote










          up vote
          1
          down vote









          I would write it as
          $$
          fleft(nright)=sqrtn+1+pi fleft(n+1right),
          $$
          Hence
          $$
          fleft(1right)=sqrt2+pi fleft(2right), fleft(2right)=sqrt3+pi fleft(3right) Rightarrow fleft(1right)=sqrt2+pisqrt3+fleft(3right)
          $$
          which means you search for $fleft(1right)$.
          $$
          fleft(n+1right)=frac1pileft(fleft(nright)^2-n-1right)
          $$






          share|cite|improve this answer












          I would write it as
          $$
          fleft(nright)=sqrtn+1+pi fleft(n+1right),
          $$
          Hence
          $$
          fleft(1right)=sqrt2+pi fleft(2right), fleft(2right)=sqrt3+pi fleft(3right) Rightarrow fleft(1right)=sqrt2+pisqrt3+fleft(3right)
          $$
          which means you search for $fleft(1right)$.
          $$
          fleft(n+1right)=frac1pileft(fleft(nright)^2-n-1right)
          $$







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Sep 3 at 8:42









          Atmos

          4,741119




          4,741119











          • I dont think so, wolfram interprets it as f(0)=0
            – Atmos
            Sep 3 at 9:51










          • I don t think so. However do you want to find a value to this ?
            – Atmos
            Sep 3 at 15:21










          • There is no value for n=0 the sequence i wrote us for n>=1
            – Atmos
            Sep 3 at 15:30






          • 1




            Hi, thank you for your reply. It is not correct, both in Matlab and WolframAlpha the sequence is not correct. link If someone can understand how to correct your formula would be perfect, yesterday I tried but I failed
            – Gionata Donati
            Sep 4 at 8:38

















          • I dont think so, wolfram interprets it as f(0)=0
            – Atmos
            Sep 3 at 9:51










          • I don t think so. However do you want to find a value to this ?
            – Atmos
            Sep 3 at 15:21










          • There is no value for n=0 the sequence i wrote us for n>=1
            – Atmos
            Sep 3 at 15:30






          • 1




            Hi, thank you for your reply. It is not correct, both in Matlab and WolframAlpha the sequence is not correct. link If someone can understand how to correct your formula would be perfect, yesterday I tried but I failed
            – Gionata Donati
            Sep 4 at 8:38
















          I dont think so, wolfram interprets it as f(0)=0
          – Atmos
          Sep 3 at 9:51




          I dont think so, wolfram interprets it as f(0)=0
          – Atmos
          Sep 3 at 9:51












          I don t think so. However do you want to find a value to this ?
          – Atmos
          Sep 3 at 15:21




          I don t think so. However do you want to find a value to this ?
          – Atmos
          Sep 3 at 15:21












          There is no value for n=0 the sequence i wrote us for n>=1
          – Atmos
          Sep 3 at 15:30




          There is no value for n=0 the sequence i wrote us for n>=1
          – Atmos
          Sep 3 at 15:30




          1




          1




          Hi, thank you for your reply. It is not correct, both in Matlab and WolframAlpha the sequence is not correct. link If someone can understand how to correct your formula would be perfect, yesterday I tried but I failed
          – Gionata Donati
          Sep 4 at 8:38





          Hi, thank you for your reply. It is not correct, both in Matlab and WolframAlpha the sequence is not correct. link If someone can understand how to correct your formula would be perfect, yesterday I tried but I failed
          – Gionata Donati
          Sep 4 at 8:38


















           

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