How can i remove the 1 on the diagonal every 4 elements while keeping my existing matrix.

If m=4 using MATLAB

1 1 -4 1 1 1 -4 1 1 1 -4 1 -4 1 1 1 1 -4 1 1 1 1 1 1 1 -4 1 1 1 -4 1 1 1 1 1 -4 1 1 1 1 -4 1 1 4 1 1 1 -4 1 1 1 1 -4 1 1 -4 -4 1 0 0 0 0 0 0 0 0 0 0 0 0 0 - 0 1 0 0 0 0 0 0 0 0 0 - 4 1 0 0 0 0 -4 0 0 0 0 0 0 0 0 0 1 1 0 OO 1 0 - 0 OO OOO OF 0 0 0 0 0 0 0 0 1 -4 1 0 0 0 0 1 0 0 0 0 1 0 1 0 0 0 0 1 0 0 0 1 4 0 0 0 0 1 0 - 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 -4 1 0 0 0 0 0 0 0 0 0 0 OOOOO -4 0 0 0 0 OO 1 -4 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 -4 0 0 -4