{{1/2, 1/2, -1/2}, {1/2, -2/2, 1/2}, {0, 1/2, 0}}.{{-1, 0, 1}, {0, 2, 0}, {1, 4, -1}} . {{1, 1, 1}, {0, 0, 2}, {-1, 1, 3}}

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