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Christmas Trees Problems: Problem 6

(White: Kd1, Qc6, Rc2, Rc5, Bb3, b4, b6, d4, d6 Black: Kb1, Qa1, Ra2, Re2, Be1, Nc7, Nc8, b2, b5, c4, d2, d3, d5, e3)

White to move and mate in 4 moves

Solution