An elementary method widely used in number theory originated from the ancient Eratosthenes sieve method. The so-called screening method can be described as: ① given "screening set". This is a set family □ (□), which depends on a parameter □. Each set □ (□) consists of a finite number of (repeatable) integers, and when □→∞, the number of elements tends to infinity. ② Given a "sieve". This is an infinite set of every given □ (□) module □, different prime numbers and different residue classes □ (□), in which 1 ≤□ (□) 0 and the proposition {□- 1, □- 1} are proved. If □ 1(□) is changed to set □2(□)={□-□, prime number □