Arithmetic derivative of sums of divisors [closed]












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Take the sums of divisors of an odd perfect square. Then check to see when the arithmetic derivative is congruent 0 mod 4






elementary-number-theory modular-arithmetic







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closed as off-topic by Cameron Williams, Jean-Claude Arbaut, Davide Giraudo, Leucippus, Cesareo Nov 27 at 2:19


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    -1














    Take the sums of divisors of an odd perfect square. Then check to see when the arithmetic derivative is congruent 0 mod 4






    elementary-number-theory modular-arithmetic







    share|cite|improve this question















    closed as off-topic by Cameron Williams, Jean-Claude Arbaut, Davide Giraudo, Leucippus, Cesareo Nov 27 at 2:19


    This question appears to be off-topic. The users who voted to close gave this specific reason:


    • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Cameron Williams, Jean-Claude Arbaut, Davide Giraudo, Leucippus, Cesareo

    If this question can be reworded to fit the rules in the help center, please edit the question.
















      -1












      -1








      -1







      Take the sums of divisors of an odd perfect square. Then check to see when the arithmetic derivative is congruent 0 mod 4






      elementary-number-theory modular-arithmetic







      share|cite|improve this question















      Take the sums of divisors of an odd perfect square. Then check to see when the arithmetic derivative is congruent 0 mod 4






      elementary-number-theory modular-arithmetic




      elementary-number-theory modular-arithmetic






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Nov 26 at 19:10









      David G. Stork

      9,69621232




      9,69621232










      asked Nov 26 at 18:54









      argamon

      756




      756




      closed as off-topic by Cameron Williams, Jean-Claude Arbaut, Davide Giraudo, Leucippus, Cesareo Nov 27 at 2:19


      This question appears to be off-topic. The users who voted to close gave this specific reason:


      • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Cameron Williams, Jean-Claude Arbaut, Davide Giraudo, Leucippus, Cesareo

      If this question can be reworded to fit the rules in the help center, please edit the question.




      closed as off-topic by Cameron Williams, Jean-Claude Arbaut, Davide Giraudo, Leucippus, Cesareo Nov 27 at 2:19


      This question appears to be off-topic. The users who voted to close gave this specific reason:


      • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Cameron Williams, Jean-Claude Arbaut, Davide Giraudo, Leucippus, Cesareo

      If this question can be reworded to fit the rules in the help center, please edit the question.






















          1 Answer
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          The first few odd $n$ for which the arithmetic derivative of $sigma(n^2)$ is divisible by $4$ are $1, 13, 15, 29, 51, 53, 63, 67, 73, 77, 79, 97, 99, 113, 123, 133, 135, 157, 161, 163, 171, 175, 185, 191, 195, 197$. This sequence doesn't seem to be in the OEIS (yet).






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          • Wow thank you so much
            – argamon
            Nov 26 at 19:12










          • are you going to add it or should I?
            – argamon
            Nov 26 at 21:36


















          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          2














          The first few odd $n$ for which the arithmetic derivative of $sigma(n^2)$ is divisible by $4$ are $1, 13, 15, 29, 51, 53, 63, 67, 73, 77, 79, 97, 99, 113, 123, 133, 135, 157, 161, 163, 171, 175, 185, 191, 195, 197$. This sequence doesn't seem to be in the OEIS (yet).






          share|cite|improve this answer





















          • Wow thank you so much
            – argamon
            Nov 26 at 19:12










          • are you going to add it or should I?
            – argamon
            Nov 26 at 21:36
















          2














          The first few odd $n$ for which the arithmetic derivative of $sigma(n^2)$ is divisible by $4$ are $1, 13, 15, 29, 51, 53, 63, 67, 73, 77, 79, 97, 99, 113, 123, 133, 135, 157, 161, 163, 171, 175, 185, 191, 195, 197$. This sequence doesn't seem to be in the OEIS (yet).






          share|cite|improve this answer





















          • Wow thank you so much
            – argamon
            Nov 26 at 19:12










          • are you going to add it or should I?
            – argamon
            Nov 26 at 21:36














          2












          2








          2






          The first few odd $n$ for which the arithmetic derivative of $sigma(n^2)$ is divisible by $4$ are $1, 13, 15, 29, 51, 53, 63, 67, 73, 77, 79, 97, 99, 113, 123, 133, 135, 157, 161, 163, 171, 175, 185, 191, 195, 197$. This sequence doesn't seem to be in the OEIS (yet).






          share|cite|improve this answer












          The first few odd $n$ for which the arithmetic derivative of $sigma(n^2)$ is divisible by $4$ are $1, 13, 15, 29, 51, 53, 63, 67, 73, 77, 79, 97, 99, 113, 123, 133, 135, 157, 161, 163, 171, 175, 185, 191, 195, 197$. This sequence doesn't seem to be in the OEIS (yet).







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Nov 26 at 19:08









          Robert Israel

          318k23207458




          318k23207458












          • Wow thank you so much
            – argamon
            Nov 26 at 19:12










          • are you going to add it or should I?
            – argamon
            Nov 26 at 21:36


















          • Wow thank you so much
            – argamon
            Nov 26 at 19:12










          • are you going to add it or should I?
            – argamon
            Nov 26 at 21:36
















          Wow thank you so much
          – argamon
          Nov 26 at 19:12




          Wow thank you so much
          – argamon
          Nov 26 at 19:12












          are you going to add it or should I?
          – argamon
          Nov 26 at 21:36




          are you going to add it or should I?
          – argamon
          Nov 26 at 21:36



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