題組內容

There are 7 problems in this test. No calculators are allowed. Write down detailed steps for the solution to each problem. Otherwise, no credits for that problem will be given. 
7. Let m and n be two positive integers, m ≤ n. Define 61e136ad50c63.jpg

(a) Show that if'n is prime, then n divides 61e136c41a947.jpgfor every i, 1 ≤i＜n.