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Matrix elements

A=[1212831823109151612851014319]A=\left[\begin{array}{rr}12 & -12 & 8 & 3 \\-1 & 8 & -2 & 3 \\1 &0 &-9 & 15 \\16 &12 &8 & 5 \\10 &14 &3 & 19\end{array}\right]
A4,1=A_{4,1}=