Prime formula.

[Lan Todak]

Hi Everyone, could anyone here help me comfirm that this calculation verifies prime numbers?
This is the calculation:

DSum(Mod((x^2−A),(2B−2x))==0,x,0.0,(B−2))

A is a reminder of a number to be tested while B is a factor of a top closest square that is used to subtract the test number. For example,

If you want to test 7, the top closest square is 3^2 or 9. B is 3 as it is a factor of 3^2. By using the square to subtract the test number, 
3^2- 7=2, u get 2. Plug into the formula, u get

DSum(Mod((x^2−2),(3⋅2−2x))==0,x,0.0,1.0)

If you want to test 19, the top closest square is 5^2 or 25. B is 5 as it is a factor of 5^2. By using the square to subtract the test number, 
5^2- 19=6, u get 6. Plug into the formula, u get

DSum(Mod((x^2−6),(5⋅2−2x))==0,x,0.0,3.0)

It works for any prime number(big or small). If u do it rite u should get all false.

Tq...

Edited December 27, 2024 by Lan Todak