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Assume that I have two number $a$ and $b$ and an $n \times n$ matrix. How can I write code which can compute all determinants of the matrices with entries $a$ or $b$. In other words, I want to see the determinant of all $2^{n^{2}}$ matrices with entries $a$ and $b$.

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  • $\begingroup$ A short example with a Mathematica code would be helpful for understanding the problem. At least show what you have tried. $\endgroup$
    – Sumit
    Commented Sep 29, 2017 at 12:16
  • $\begingroup$ Do you need the multiplicity of each possible determinant value? $\endgroup$
    – Coolwater
    Commented Sep 29, 2017 at 12:23
  • $\begingroup$ A.Mpi, please see Michael E2's comment here which is our community's standard welcome message to new users. $\endgroup$
    – kglr
    Commented Sep 29, 2017 at 12:57

1 Answer 1

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n = 3; 
matrices = Tuples[{a, b}, {n, n}];
Length@matrices

512

Det /@ matrices // Simplify // Short

{0, 0, 0, 0, 0, 0, 0, 0, 0, 0,-a (a-b)^2, -a (a-b)^2, a (a-b)^2, <<486>>, (a-b)^2 b, -(a-b)^2 b, -(a-b)^2 b, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}

Det /@ matrices // Simplify // Tally // Grid[#, Dividers -> All] &

enter image description here

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