What is the minimum distance between vertices on an integer grid with the form $(m(m+2), 0)p + (m, 1)q$?












0












$begingroup$


Suppose, for given $m > 0$, we have a set of points of the form $v = (m(m+2), 0)p + (m, 1)q$, with $p, q, m$ integers. What is the minimum distance between two (distinct ones) of them?



Here is the square distance between any point and the origin:
$|v|^2 = (pm^2 + 2pm + qm)^2 + q^2,$



we need to find the $p, q$ that minimizes this distance given $m > 0$.



In practice it is easy enough to check a few points, and find the optimum by trial and error, but I am wondering if there is a closed form solution.



Background: this came up while working on this question: How many colors is necessary so that a rectangle always covers no color more than once?. See the second last conjecture.



(Note: I am not sure if there are more appropriate tags.)










share|cite|improve this question











$endgroup$

















    0












    $begingroup$


    Suppose, for given $m > 0$, we have a set of points of the form $v = (m(m+2), 0)p + (m, 1)q$, with $p, q, m$ integers. What is the minimum distance between two (distinct ones) of them?



    Here is the square distance between any point and the origin:
    $|v|^2 = (pm^2 + 2pm + qm)^2 + q^2,$



    we need to find the $p, q$ that minimizes this distance given $m > 0$.



    In practice it is easy enough to check a few points, and find the optimum by trial and error, but I am wondering if there is a closed form solution.



    Background: this came up while working on this question: How many colors is necessary so that a rectangle always covers no color more than once?. See the second last conjecture.



    (Note: I am not sure if there are more appropriate tags.)










    share|cite|improve this question











    $endgroup$















      0












      0








      0





      $begingroup$


      Suppose, for given $m > 0$, we have a set of points of the form $v = (m(m+2), 0)p + (m, 1)q$, with $p, q, m$ integers. What is the minimum distance between two (distinct ones) of them?



      Here is the square distance between any point and the origin:
      $|v|^2 = (pm^2 + 2pm + qm)^2 + q^2,$



      we need to find the $p, q$ that minimizes this distance given $m > 0$.



      In practice it is easy enough to check a few points, and find the optimum by trial and error, but I am wondering if there is a closed form solution.



      Background: this came up while working on this question: How many colors is necessary so that a rectangle always covers no color more than once?. See the second last conjecture.



      (Note: I am not sure if there are more appropriate tags.)










      share|cite|improve this question











      $endgroup$




      Suppose, for given $m > 0$, we have a set of points of the form $v = (m(m+2), 0)p + (m, 1)q$, with $p, q, m$ integers. What is the minimum distance between two (distinct ones) of them?



      Here is the square distance between any point and the origin:
      $|v|^2 = (pm^2 + 2pm + qm)^2 + q^2,$



      we need to find the $p, q$ that minimizes this distance given $m > 0$.



      In practice it is easy enough to check a few points, and find the optimum by trial and error, but I am wondering if there is a closed form solution.



      Background: this came up while working on this question: How many colors is necessary so that a rectangle always covers no color more than once?. See the second last conjecture.



      (Note: I am not sure if there are more appropriate tags.)







      integer-programming






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Dec 14 '18 at 22:57







      Herman Tulleken

















      asked Dec 14 '18 at 22:36









      Herman TullekenHerman Tulleken

      968620




      968620






















          1 Answer
          1






          active

          oldest

          votes


















          0












          $begingroup$

          Since $v^2$ is a sum of squares of integers, and it's not $0$, then it must be $1$ (if we can find such a solution). There are two choices:



          Case 1: $q=0$ and $pm^2+2pm+qm=pm1$. I can easily guess a solution for
          $pm^2+2pm=-1$: $p=1$ and $m=-1$



          Case 2: $q=pm 1$ and $pm^2+2pm+qm=0$. Same $p$ and $m$ as above also verify this case.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            I realized now my question did not specify to find $p, q$ given $m$. I will update my question.
            $endgroup$
            – Herman Tulleken
            Dec 14 '18 at 22:55











          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%2f3039961%2fwhat-is-the-minimum-distance-between-vertices-on-an-integer-grid-with-the-form%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









          0












          $begingroup$

          Since $v^2$ is a sum of squares of integers, and it's not $0$, then it must be $1$ (if we can find such a solution). There are two choices:



          Case 1: $q=0$ and $pm^2+2pm+qm=pm1$. I can easily guess a solution for
          $pm^2+2pm=-1$: $p=1$ and $m=-1$



          Case 2: $q=pm 1$ and $pm^2+2pm+qm=0$. Same $p$ and $m$ as above also verify this case.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            I realized now my question did not specify to find $p, q$ given $m$. I will update my question.
            $endgroup$
            – Herman Tulleken
            Dec 14 '18 at 22:55
















          0












          $begingroup$

          Since $v^2$ is a sum of squares of integers, and it's not $0$, then it must be $1$ (if we can find such a solution). There are two choices:



          Case 1: $q=0$ and $pm^2+2pm+qm=pm1$. I can easily guess a solution for
          $pm^2+2pm=-1$: $p=1$ and $m=-1$



          Case 2: $q=pm 1$ and $pm^2+2pm+qm=0$. Same $p$ and $m$ as above also verify this case.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            I realized now my question did not specify to find $p, q$ given $m$. I will update my question.
            $endgroup$
            – Herman Tulleken
            Dec 14 '18 at 22:55














          0












          0








          0





          $begingroup$

          Since $v^2$ is a sum of squares of integers, and it's not $0$, then it must be $1$ (if we can find such a solution). There are two choices:



          Case 1: $q=0$ and $pm^2+2pm+qm=pm1$. I can easily guess a solution for
          $pm^2+2pm=-1$: $p=1$ and $m=-1$



          Case 2: $q=pm 1$ and $pm^2+2pm+qm=0$. Same $p$ and $m$ as above also verify this case.






          share|cite|improve this answer









          $endgroup$



          Since $v^2$ is a sum of squares of integers, and it's not $0$, then it must be $1$ (if we can find such a solution). There are two choices:



          Case 1: $q=0$ and $pm^2+2pm+qm=pm1$. I can easily guess a solution for
          $pm^2+2pm=-1$: $p=1$ and $m=-1$



          Case 2: $q=pm 1$ and $pm^2+2pm+qm=0$. Same $p$ and $m$ as above also verify this case.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Dec 14 '18 at 22:51









          AndreiAndrei

          12.6k21128




          12.6k21128












          • $begingroup$
            I realized now my question did not specify to find $p, q$ given $m$. I will update my question.
            $endgroup$
            – Herman Tulleken
            Dec 14 '18 at 22:55


















          • $begingroup$
            I realized now my question did not specify to find $p, q$ given $m$. I will update my question.
            $endgroup$
            – Herman Tulleken
            Dec 14 '18 at 22:55
















          $begingroup$
          I realized now my question did not specify to find $p, q$ given $m$. I will update my question.
          $endgroup$
          – Herman Tulleken
          Dec 14 '18 at 22:55




          $begingroup$
          I realized now my question did not specify to find $p, q$ given $m$. I will update my question.
          $endgroup$
          – Herman Tulleken
          Dec 14 '18 at 22:55


















          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%2f3039961%2fwhat-is-the-minimum-distance-between-vertices-on-an-integer-grid-with-the-form%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

          Le Mesnil-Réaume

          Ida-Boy-Ed-Garten

          web3.py web3.isConnected() returns false always