Problem
2021 AIME II Problem 3
Find the number of permutations x_1, x_2, x_3, x_4, x_5 of numbers 1, 2, 3, 4, 5 such that the sum of five products x_1x_2x_3 + x_2x_3x_4 + x_3x_4x_5 + x_4x_5x_1 + x_5x_1x_2 is divisible by 3.
Leading zeroes must be inputted, so if your answer is 34, then input 034
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