(inverse {{0,1,2,3},{1,0,4,14},{1,0,2,11},{0,1,3,9}})* {{4,-1,1,-1},{1,3,0,0},{0,1,2,1},{0,0,0,3}}*{{0,1,2,3},{1,0,4,14},{1,0,2,11},{0,1,3,9}}

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