mathematical conjecture

For any natural number a,

(1) A. If a is even, divide by 2.

B If a is odd, multiply it by 3 and add 1.

Write down the number as B.

(2) Replace A with B to perform the operation of (1) again.

After a few steps, the number is 1.

This conjecture is called the corner-valley conjecture,

So far, no one can prove it.