We have n empty boxes, so let’s recolor those boxes with m colors. The boxes are put in a line. It is not allowed to color any adjacent boxes with the same color. Boxes i and i+1 are said to be adjacent for every i,1≤i≤n. And we also want the total number of different colors of the n boxes being exactly k. Two ways are considered different if and only if there is at least one box being colored with different colors.
We have n empty boxes, so let’s recolor those boxes with m colors. The boxes are put in a line. It is not allowed to color any adjacent boxes with the same color. Boxes i and i+1 are said to be adjacent for every i,1≤i≤n. And we also want the total number of different colors of the n boxes being exactly k. Two ways are considered different if and only if there is at least one box being colored with different colors.
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