Matrices & Determinants · Adjoint and inverse properties

Let

A = \begin{bmatrix} 1 & 1 & 2\\ -2 & 0 & 1\\ 1 & 3 & 5\end{bmatrix}.

Then the sum of all elements of the matrix

\operatorname{adj}(\operatorname{adj}(2(\operatorname{adj}A)^{-1}))

is equal to:

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