Reverse engineering a math magic trick involving matrices.












25














This problem was brought up by my mother from a corporate party along with a question on how that worked.



There was a showman who asked to tell him a number from $10$ to $99$ (If i'm not mistaken). The number $83$ was named after which he took a piece of paper and quickly put down a matrix (note he did that fast):



$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & 2 & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



If you take a closer look every row, column and diagonal has the sum of $83$. Moreover consider the corners of the matrix also have the sum of $83$. For example:
$$
begin{bmatrix}
colorred{8} & colorred{11} & 63 & 1\
colorred{62} & colorred{2} & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Also the central square is $83$ in sum as well:
$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & colorred{2} & colorred{7} & 12\
3 & colorred{65} & colorred{9} & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Clearly numbers $1,2,3,4,5,6,7,8,9,10,11,12$ are filled in in a circular manner. And then consequent $62, 63, 64, 65$ are as well. I'm not very familial with linear algebra so my question is:




What was that rule he used to build it? Can we construct a matrix with the same properties given a random number in some range? Is it possible to build a similar one but for $5times 5$, $6times 6$ or $Ntimes N$ matrix?











share|cite|improve this question
























  • What kind of show was that?
    – lcv
    Dec 22 at 13:32






  • 10




    It’s hard to imagine a less geeky show :-)
    – lcv
    Dec 22 at 13:38






  • 8




    This feels more like recreational mathematics than linear algebra.
    – Andreas Rejbrand
    Dec 22 at 16:50






  • 1




    Reminds me of a paper I read before about constructing magic squares. Have a look at this: researchgate.net/publication/…
    – Zushauque
    Dec 22 at 20:00






  • 1




    To show that you can get any sum on the rows, columns, and two main diagonals for any $N times N$ magic square ($N ge 4$), see my Answer here: math.stackexchange.com/questions/1992336/…
    – Bram28
    Dec 23 at 15:40


















25














This problem was brought up by my mother from a corporate party along with a question on how that worked.



There was a showman who asked to tell him a number from $10$ to $99$ (If i'm not mistaken). The number $83$ was named after which he took a piece of paper and quickly put down a matrix (note he did that fast):



$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & 2 & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



If you take a closer look every row, column and diagonal has the sum of $83$. Moreover consider the corners of the matrix also have the sum of $83$. For example:
$$
begin{bmatrix}
colorred{8} & colorred{11} & 63 & 1\
colorred{62} & colorred{2} & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Also the central square is $83$ in sum as well:
$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & colorred{2} & colorred{7} & 12\
3 & colorred{65} & colorred{9} & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Clearly numbers $1,2,3,4,5,6,7,8,9,10,11,12$ are filled in in a circular manner. And then consequent $62, 63, 64, 65$ are as well. I'm not very familial with linear algebra so my question is:




What was that rule he used to build it? Can we construct a matrix with the same properties given a random number in some range? Is it possible to build a similar one but for $5times 5$, $6times 6$ or $Ntimes N$ matrix?











share|cite|improve this question
























  • What kind of show was that?
    – lcv
    Dec 22 at 13:32






  • 10




    It’s hard to imagine a less geeky show :-)
    – lcv
    Dec 22 at 13:38






  • 8




    This feels more like recreational mathematics than linear algebra.
    – Andreas Rejbrand
    Dec 22 at 16:50






  • 1




    Reminds me of a paper I read before about constructing magic squares. Have a look at this: researchgate.net/publication/…
    – Zushauque
    Dec 22 at 20:00






  • 1




    To show that you can get any sum on the rows, columns, and two main diagonals for any $N times N$ magic square ($N ge 4$), see my Answer here: math.stackexchange.com/questions/1992336/…
    – Bram28
    Dec 23 at 15:40
















25












25








25


14





This problem was brought up by my mother from a corporate party along with a question on how that worked.



There was a showman who asked to tell him a number from $10$ to $99$ (If i'm not mistaken). The number $83$ was named after which he took a piece of paper and quickly put down a matrix (note he did that fast):



$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & 2 & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



If you take a closer look every row, column and diagonal has the sum of $83$. Moreover consider the corners of the matrix also have the sum of $83$. For example:
$$
begin{bmatrix}
colorred{8} & colorred{11} & 63 & 1\
colorred{62} & colorred{2} & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Also the central square is $83$ in sum as well:
$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & colorred{2} & colorred{7} & 12\
3 & colorred{65} & colorred{9} & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Clearly numbers $1,2,3,4,5,6,7,8,9,10,11,12$ are filled in in a circular manner. And then consequent $62, 63, 64, 65$ are as well. I'm not very familial with linear algebra so my question is:




What was that rule he used to build it? Can we construct a matrix with the same properties given a random number in some range? Is it possible to build a similar one but for $5times 5$, $6times 6$ or $Ntimes N$ matrix?











share|cite|improve this question















This problem was brought up by my mother from a corporate party along with a question on how that worked.



There was a showman who asked to tell him a number from $10$ to $99$ (If i'm not mistaken). The number $83$ was named after which he took a piece of paper and quickly put down a matrix (note he did that fast):



$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & 2 & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



If you take a closer look every row, column and diagonal has the sum of $83$. Moreover consider the corners of the matrix also have the sum of $83$. For example:
$$
begin{bmatrix}
colorred{8} & colorred{11} & 63 & 1\
colorred{62} & colorred{2} & 7 & 12\
3 & 65 & 9 & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Also the central square is $83$ in sum as well:
$$
begin{bmatrix}
8 & 11 & 63 & 1\
62 & colorred{2} & colorred{7} & 12\
3 & colorred{65} & colorred{9} & 6 \
10 & 5 & 4 & 64
end{bmatrix}
$$



Clearly numbers $1,2,3,4,5,6,7,8,9,10,11,12$ are filled in in a circular manner. And then consequent $62, 63, 64, 65$ are as well. I'm not very familial with linear algebra so my question is:




What was that rule he used to build it? Can we construct a matrix with the same properties given a random number in some range? Is it possible to build a similar one but for $5times 5$, $6times 6$ or $Ntimes N$ matrix?








recreational-mathematics magic-square






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 22 at 21:20









anomaly

17.3k42663




17.3k42663










asked Dec 22 at 12:48









roman

1,92921221




1,92921221












  • What kind of show was that?
    – lcv
    Dec 22 at 13:32






  • 10




    It’s hard to imagine a less geeky show :-)
    – lcv
    Dec 22 at 13:38






  • 8




    This feels more like recreational mathematics than linear algebra.
    – Andreas Rejbrand
    Dec 22 at 16:50






  • 1




    Reminds me of a paper I read before about constructing magic squares. Have a look at this: researchgate.net/publication/…
    – Zushauque
    Dec 22 at 20:00






  • 1




    To show that you can get any sum on the rows, columns, and two main diagonals for any $N times N$ magic square ($N ge 4$), see my Answer here: math.stackexchange.com/questions/1992336/…
    – Bram28
    Dec 23 at 15:40




















  • What kind of show was that?
    – lcv
    Dec 22 at 13:32






  • 10




    It’s hard to imagine a less geeky show :-)
    – lcv
    Dec 22 at 13:38






  • 8




    This feels more like recreational mathematics than linear algebra.
    – Andreas Rejbrand
    Dec 22 at 16:50






  • 1




    Reminds me of a paper I read before about constructing magic squares. Have a look at this: researchgate.net/publication/…
    – Zushauque
    Dec 22 at 20:00






  • 1




    To show that you can get any sum on the rows, columns, and two main diagonals for any $N times N$ magic square ($N ge 4$), see my Answer here: math.stackexchange.com/questions/1992336/…
    – Bram28
    Dec 23 at 15:40


















What kind of show was that?
– lcv
Dec 22 at 13:32




What kind of show was that?
– lcv
Dec 22 at 13:32




10




10




It’s hard to imagine a less geeky show :-)
– lcv
Dec 22 at 13:38




It’s hard to imagine a less geeky show :-)
– lcv
Dec 22 at 13:38




8




8




This feels more like recreational mathematics than linear algebra.
– Andreas Rejbrand
Dec 22 at 16:50




This feels more like recreational mathematics than linear algebra.
– Andreas Rejbrand
Dec 22 at 16:50




1




1




Reminds me of a paper I read before about constructing magic squares. Have a look at this: researchgate.net/publication/…
– Zushauque
Dec 22 at 20:00




Reminds me of a paper I read before about constructing magic squares. Have a look at this: researchgate.net/publication/…
– Zushauque
Dec 22 at 20:00




1




1




To show that you can get any sum on the rows, columns, and two main diagonals for any $N times N$ magic square ($N ge 4$), see my Answer here: math.stackexchange.com/questions/1992336/…
– Bram28
Dec 23 at 15:40






To show that you can get any sum on the rows, columns, and two main diagonals for any $N times N$ magic square ($N ge 4$), see my Answer here: math.stackexchange.com/questions/1992336/…
– Bram28
Dec 23 at 15:40












3 Answers
3






active

oldest

votes


















32














This is all based on the amazing matrix $$pmatrix{8&11&14&1\13&2&7&12\3&16&9&6\10&5&4&15}$$
Note that this works for $34$. For $34+n$ you just replace $13,14,15,16$ with $13+n,14+n,15+n,16+n$. I do not know what the showman's backup plan for numbers below $34$ is.



EDIT: There is a Numberphile video on YouTube on this exact trick.






share|cite|improve this answer



















  • 5




    I also believe it was not 10, but rather some larger two digit number
    – roman
    Dec 22 at 13:19






  • 2




    Thanks for sharing a link to the video! Also it looks like magic does not exist after all :)
    – roman
    Dec 22 at 15:30






  • 1




    It's possible that his backup plan was to subtract some number from those four.
    – Jarred Allen
    Dec 23 at 18:36










  • @JarredAllen Or perhaps use a smaller matrix? Subtract all numbers from 100, effectively inverting the trick? No clue, but there are possibilities indeed.
    – Mast
    Dec 24 at 6:45



















16














He did not write down 'a matrix'. He wrote down a magic square.



There are various algorithms for constructing them, the easiest to do mentally is to start with a generic starter matrix you memoize:



 A  1 12  7
11 8 B 2
5 10 3 C
4 D 6 9


And solve for A, B, C, D for your target number. With some practice you can do this super fast.






share|cite|improve this answer



















  • 8




    Of course it is a matrix as well.
    – Jannik Pitt
    Dec 22 at 13:27






  • 4




    @JannikPitt Of course. I just remarked on it as if someone arriving by private helicopter to do grocery shopping is described as "arriving by vehicle".
    – orlp
    Dec 22 at 17:16



















6














Observe that the numbers in the sixties lie on different rows, different columns and different quadrants. If you increase them simultaneously, all the twelve sums increase by the same amount.



In the pure magic square (numbers $1$ to $16$), the sum is $34$, hence if suffices to add $83-34=49$ to these four elements.



It would be more logical to request a sum in the range $[34,83]$ so that all elements are at most two-digit naturals.



For stronger mystification, you can split the required increment in two or more and adjust on the other possible groups.






share|cite|improve this answer























    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%2f3049428%2freverse-engineering-a-math-magic-trick-involving-matrices%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    3 Answers
    3






    active

    oldest

    votes








    3 Answers
    3






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    32














    This is all based on the amazing matrix $$pmatrix{8&11&14&1\13&2&7&12\3&16&9&6\10&5&4&15}$$
    Note that this works for $34$. For $34+n$ you just replace $13,14,15,16$ with $13+n,14+n,15+n,16+n$. I do not know what the showman's backup plan for numbers below $34$ is.



    EDIT: There is a Numberphile video on YouTube on this exact trick.






    share|cite|improve this answer



















    • 5




      I also believe it was not 10, but rather some larger two digit number
      – roman
      Dec 22 at 13:19






    • 2




      Thanks for sharing a link to the video! Also it looks like magic does not exist after all :)
      – roman
      Dec 22 at 15:30






    • 1




      It's possible that his backup plan was to subtract some number from those four.
      – Jarred Allen
      Dec 23 at 18:36










    • @JarredAllen Or perhaps use a smaller matrix? Subtract all numbers from 100, effectively inverting the trick? No clue, but there are possibilities indeed.
      – Mast
      Dec 24 at 6:45
















    32














    This is all based on the amazing matrix $$pmatrix{8&11&14&1\13&2&7&12\3&16&9&6\10&5&4&15}$$
    Note that this works for $34$. For $34+n$ you just replace $13,14,15,16$ with $13+n,14+n,15+n,16+n$. I do not know what the showman's backup plan for numbers below $34$ is.



    EDIT: There is a Numberphile video on YouTube on this exact trick.






    share|cite|improve this answer



















    • 5




      I also believe it was not 10, but rather some larger two digit number
      – roman
      Dec 22 at 13:19






    • 2




      Thanks for sharing a link to the video! Also it looks like magic does not exist after all :)
      – roman
      Dec 22 at 15:30






    • 1




      It's possible that his backup plan was to subtract some number from those four.
      – Jarred Allen
      Dec 23 at 18:36










    • @JarredAllen Or perhaps use a smaller matrix? Subtract all numbers from 100, effectively inverting the trick? No clue, but there are possibilities indeed.
      – Mast
      Dec 24 at 6:45














    32












    32








    32






    This is all based on the amazing matrix $$pmatrix{8&11&14&1\13&2&7&12\3&16&9&6\10&5&4&15}$$
    Note that this works for $34$. For $34+n$ you just replace $13,14,15,16$ with $13+n,14+n,15+n,16+n$. I do not know what the showman's backup plan for numbers below $34$ is.



    EDIT: There is a Numberphile video on YouTube on this exact trick.






    share|cite|improve this answer














    This is all based on the amazing matrix $$pmatrix{8&11&14&1\13&2&7&12\3&16&9&6\10&5&4&15}$$
    Note that this works for $34$. For $34+n$ you just replace $13,14,15,16$ with $13+n,14+n,15+n,16+n$. I do not know what the showman's backup plan for numbers below $34$ is.



    EDIT: There is a Numberphile video on YouTube on this exact trick.







    share|cite|improve this answer














    share|cite|improve this answer



    share|cite|improve this answer








    edited Dec 23 at 21:43









    Rodrigo de Azevedo

    12.8k41854




    12.8k41854










    answered Dec 22 at 13:05









    SmileyCraft

    2,398413




    2,398413








    • 5




      I also believe it was not 10, but rather some larger two digit number
      – roman
      Dec 22 at 13:19






    • 2




      Thanks for sharing a link to the video! Also it looks like magic does not exist after all :)
      – roman
      Dec 22 at 15:30






    • 1




      It's possible that his backup plan was to subtract some number from those four.
      – Jarred Allen
      Dec 23 at 18:36










    • @JarredAllen Or perhaps use a smaller matrix? Subtract all numbers from 100, effectively inverting the trick? No clue, but there are possibilities indeed.
      – Mast
      Dec 24 at 6:45














    • 5




      I also believe it was not 10, but rather some larger two digit number
      – roman
      Dec 22 at 13:19






    • 2




      Thanks for sharing a link to the video! Also it looks like magic does not exist after all :)
      – roman
      Dec 22 at 15:30






    • 1




      It's possible that his backup plan was to subtract some number from those four.
      – Jarred Allen
      Dec 23 at 18:36










    • @JarredAllen Or perhaps use a smaller matrix? Subtract all numbers from 100, effectively inverting the trick? No clue, but there are possibilities indeed.
      – Mast
      Dec 24 at 6:45








    5




    5




    I also believe it was not 10, but rather some larger two digit number
    – roman
    Dec 22 at 13:19




    I also believe it was not 10, but rather some larger two digit number
    – roman
    Dec 22 at 13:19




    2




    2




    Thanks for sharing a link to the video! Also it looks like magic does not exist after all :)
    – roman
    Dec 22 at 15:30




    Thanks for sharing a link to the video! Also it looks like magic does not exist after all :)
    – roman
    Dec 22 at 15:30




    1




    1




    It's possible that his backup plan was to subtract some number from those four.
    – Jarred Allen
    Dec 23 at 18:36




    It's possible that his backup plan was to subtract some number from those four.
    – Jarred Allen
    Dec 23 at 18:36












    @JarredAllen Or perhaps use a smaller matrix? Subtract all numbers from 100, effectively inverting the trick? No clue, but there are possibilities indeed.
    – Mast
    Dec 24 at 6:45




    @JarredAllen Or perhaps use a smaller matrix? Subtract all numbers from 100, effectively inverting the trick? No clue, but there are possibilities indeed.
    – Mast
    Dec 24 at 6:45











    16














    He did not write down 'a matrix'. He wrote down a magic square.



    There are various algorithms for constructing them, the easiest to do mentally is to start with a generic starter matrix you memoize:



     A  1 12  7
    11 8 B 2
    5 10 3 C
    4 D 6 9


    And solve for A, B, C, D for your target number. With some practice you can do this super fast.






    share|cite|improve this answer



















    • 8




      Of course it is a matrix as well.
      – Jannik Pitt
      Dec 22 at 13:27






    • 4




      @JannikPitt Of course. I just remarked on it as if someone arriving by private helicopter to do grocery shopping is described as "arriving by vehicle".
      – orlp
      Dec 22 at 17:16
















    16














    He did not write down 'a matrix'. He wrote down a magic square.



    There are various algorithms for constructing them, the easiest to do mentally is to start with a generic starter matrix you memoize:



     A  1 12  7
    11 8 B 2
    5 10 3 C
    4 D 6 9


    And solve for A, B, C, D for your target number. With some practice you can do this super fast.






    share|cite|improve this answer



















    • 8




      Of course it is a matrix as well.
      – Jannik Pitt
      Dec 22 at 13:27






    • 4




      @JannikPitt Of course. I just remarked on it as if someone arriving by private helicopter to do grocery shopping is described as "arriving by vehicle".
      – orlp
      Dec 22 at 17:16














    16












    16








    16






    He did not write down 'a matrix'. He wrote down a magic square.



    There are various algorithms for constructing them, the easiest to do mentally is to start with a generic starter matrix you memoize:



     A  1 12  7
    11 8 B 2
    5 10 3 C
    4 D 6 9


    And solve for A, B, C, D for your target number. With some practice you can do this super fast.






    share|cite|improve this answer














    He did not write down 'a matrix'. He wrote down a magic square.



    There are various algorithms for constructing them, the easiest to do mentally is to start with a generic starter matrix you memoize:



     A  1 12  7
    11 8 B 2
    5 10 3 C
    4 D 6 9


    And solve for A, B, C, D for your target number. With some practice you can do this super fast.







    share|cite|improve this answer














    share|cite|improve this answer



    share|cite|improve this answer








    edited Dec 22 at 17:16

























    answered Dec 22 at 13:06









    orlp

    7,3411230




    7,3411230








    • 8




      Of course it is a matrix as well.
      – Jannik Pitt
      Dec 22 at 13:27






    • 4




      @JannikPitt Of course. I just remarked on it as if someone arriving by private helicopter to do grocery shopping is described as "arriving by vehicle".
      – orlp
      Dec 22 at 17:16














    • 8




      Of course it is a matrix as well.
      – Jannik Pitt
      Dec 22 at 13:27






    • 4




      @JannikPitt Of course. I just remarked on it as if someone arriving by private helicopter to do grocery shopping is described as "arriving by vehicle".
      – orlp
      Dec 22 at 17:16








    8




    8




    Of course it is a matrix as well.
    – Jannik Pitt
    Dec 22 at 13:27




    Of course it is a matrix as well.
    – Jannik Pitt
    Dec 22 at 13:27




    4




    4




    @JannikPitt Of course. I just remarked on it as if someone arriving by private helicopter to do grocery shopping is described as "arriving by vehicle".
    – orlp
    Dec 22 at 17:16




    @JannikPitt Of course. I just remarked on it as if someone arriving by private helicopter to do grocery shopping is described as "arriving by vehicle".
    – orlp
    Dec 22 at 17:16











    6














    Observe that the numbers in the sixties lie on different rows, different columns and different quadrants. If you increase them simultaneously, all the twelve sums increase by the same amount.



    In the pure magic square (numbers $1$ to $16$), the sum is $34$, hence if suffices to add $83-34=49$ to these four elements.



    It would be more logical to request a sum in the range $[34,83]$ so that all elements are at most two-digit naturals.



    For stronger mystification, you can split the required increment in two or more and adjust on the other possible groups.






    share|cite|improve this answer




























      6














      Observe that the numbers in the sixties lie on different rows, different columns and different quadrants. If you increase them simultaneously, all the twelve sums increase by the same amount.



      In the pure magic square (numbers $1$ to $16$), the sum is $34$, hence if suffices to add $83-34=49$ to these four elements.



      It would be more logical to request a sum in the range $[34,83]$ so that all elements are at most two-digit naturals.



      For stronger mystification, you can split the required increment in two or more and adjust on the other possible groups.






      share|cite|improve this answer


























        6












        6








        6






        Observe that the numbers in the sixties lie on different rows, different columns and different quadrants. If you increase them simultaneously, all the twelve sums increase by the same amount.



        In the pure magic square (numbers $1$ to $16$), the sum is $34$, hence if suffices to add $83-34=49$ to these four elements.



        It would be more logical to request a sum in the range $[34,83]$ so that all elements are at most two-digit naturals.



        For stronger mystification, you can split the required increment in two or more and adjust on the other possible groups.






        share|cite|improve this answer














        Observe that the numbers in the sixties lie on different rows, different columns and different quadrants. If you increase them simultaneously, all the twelve sums increase by the same amount.



        In the pure magic square (numbers $1$ to $16$), the sum is $34$, hence if suffices to add $83-34=49$ to these four elements.



        It would be more logical to request a sum in the range $[34,83]$ so that all elements are at most two-digit naturals.



        For stronger mystification, you can split the required increment in two or more and adjust on the other possible groups.







        share|cite|improve this answer














        share|cite|improve this answer



        share|cite|improve this answer








        edited Dec 22 at 13:55

























        answered Dec 22 at 13:49









        Yves Daoust

        124k671221




        124k671221






























            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.





            Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


            Please pay close attention to the following guidance:


            • 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.


            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%2f3049428%2freverse-engineering-a-math-magic-trick-involving-matrices%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

            數位音樂下載

            When can things happen in Etherscan, such as the picture below?

            格利澤436b