A (2k+1) by (2k+1) by (2k+1) cube, where k is a positive integer, is painted in the same manner as the 5 by 5 by 5 cube with white squares in the corners. Again, the cube is cut into 1 by 1 by 1 cubes. (i) In terms of k, how many of these cubes have exactly two white faces? Explain how you obtained your answer. (ii) Prove that there is no value of k for which the number of cubes having at least two white faces is 2006.
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