Find RHS from LHS.

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$A=\left[ \begin{array}{cc} 0 & 1 \\ 1 & 0 \\ \end{array} \right]<==>\left[\begin{array}{cccc} 0 & 0 & 1 & 1 \\ 0 & 0 & 1 & 1 \\ 1 & 1 & 0 & 0 \\ 1 & 1 & 0 & 0 \\ \end{array}\right]=A^{'}$
$B=\left[ \begin{array}{ccc} 0 & 1 & 1 \\ 1 & 0 & 0 \\ 1 & 0 & 0 \\ \end{array} \right]<===>\left[ \begin{array}{cccccc} 0 & 0 & 1 & 1 & 1 & 1 \\ 0 & 0 & 1 & 1 & 1 & 1 \\ 1 & 1 & 0 & 0 & 0 & 0 \\ 1 & 1 & 0 & 0 & 0 & 0 \\ 1 & 1 & 0 & 0 & 0 & 0 \\ 1 & 1 & 0 & 0 & 0 & 0 \\ \end{array} \right]=B^{'}$

From the above we can obtain the RHS matrices from LHS by replacing $k\times k$ block submatrices in the corresponding entries of A. Here, in the above example $k=2$. Here My question is how to denote RHS matrix in terms of LHS in general?

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Let $E_k$ denote the $k\times k$-matrix with entries only $1$, hence $$ E_k = \begin{pmatrix} 1 & \cdots & 1 \\ \vdots & \ddots & \vdots \\ 1 & \cdots & 1 \end{pmatrix} $$ Then, with $\otimes$ denoting the Kronecker product, we have $$ A' = A \otimes E_2, B' = B \otimes E_2 $$