1 2 3 4 5 6 7 8 9 10 11
n = int(input()) A3 = [0]*3 A5 = [0]*3 for i in range(n): x = int(input()) if x%5 == 0: A5[x%3] += 1 else: A3[x%3] += 1 s = 0 for i in range(1,A5[0]+1): s += i print(A3[0]*A5[0]+A3[2]*A5[1]+A3[1]*A5[2]+A5[1]*A5[2]+s)