+306 Find the number of ways of arranging the numbers 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 in a 3x4 array (with three rows and four columns), so that the sum of the numbers in each column is divisible by 3. Each number must appear exactly
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+4 
+53 
+152 
+105 Mar 17, 2020
Suppose f(x), g(x), and h(x) are all linear functions, and j(x) and k(x) are defined by $$j(x) = \max\{f(x),g(x),h(x)\},$$ $$k(x) = \min\{f(x),g(x),h(x)\}.$$. This means that, for each x, we define j(x) to be equal to either f(x), g(x), or
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