Some even expressed as 1+1 or 1-2, 1-4, 1-c, 1+2 can also be expressed as 1-3

Abstract

According to known conclusions, even numbers can be expressed as 1+2, 1+5, 3+2, 1+c. So this paper derives conclusions partial even expressed as 1+1 or 1-2, 1-4, 1-c, 1+2 can also be expressed as 1-3.