The switching formula is 2:

2 can be divided into 1 and 1, 1 and 1, which add up to 2.

The switching formula is 3:

3 can be divided into 1 and 2, or 2 and 1.

1 and 2 add up to 3, 2 and 1 add up to 3.

The switching formula is 4:

4 can be divided into 1 and 3,2 and 2,3 and 1.

1 and 3 add up to 4, 2 and 2 add up to 4, 3 and 1 add up to 4.

The switching formula is 7:

7 can be divided into 0 and 7, and 0 and 7 synthesize 7.

7 can be divided into 1 and 6, 1 and 6 to synthesize 7.

7 can be divided into 2 and 5, and 2 and 5 synthesize 7.

7 can be divided into 3 and 4, and 3 and 4 synthesize 7.

resolution into factors

Writing a positive integer as the product of several divisors is of great significance in algebra, cryptography, computational complexity theory and quantum computers.

The key of factorization is to find the factor (divisor). Factorization can derive a complete list of factors, and the power will increase from zero until it is equal to this number. For example, because 45= 3×3×5, 45 can be divisible by 1, 5, 3, 9, 15 and 45. Accordingly, divisor decomposition only contains divisor factors.