suppose sequence k integer a a_1 a_2 dot a_k a_i geq 2 a sequence prime integer p p_1 p_2 dot p_k call suitable sequence a a_1 divisible p_1 a_2 divisible p_2 a sequence prime integer p call friendly unique integer sequence a sequence a call ideal sequence p suitable a friendly ie sequence p suitable a friendly for example sequence 2 4 16 ideal sequence 2 4 6 ideal exist sequence p 2 2 3 suitable a friendlyyou give n different integer x_1 x_2 x_n you choose exactly k way form ideal sequence report impossible note integer choose