About finding the inverse of a matrix

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I am solving a linear algebra problem and this matrix came up from a system of linear equations.

$A = \begin{pmatrix} 1 & 2 & \cdots & n \\ 1 & 2^2 & \cdots & n^2 \\ \vdots & & &\vdots &\\ 1 & 2^n & \cdots & n^n \end{pmatrix} $

I do not know how to check if my system has an unique solution or not (or the matrix is invertible) in this case.

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The way to go is to run, say, LU-factorisation using one of broadly available codes allowing evaluation of the matrix condition ratio. Run the program for n=2,3,4... to see the pattern. You will probably see that the condition ratio is growing with each next n (in numerical sense, the matrix looks "bad" to me in general). As soon as the condition ratio reaches the value of about 10**16, the matrix (and all the others for n larger than the found one) is singular in numerical sense, because the computer operates with double precision variables, ie. it stores 16 significant digits only.