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prime number finder.
well the other day i noticed that the diferance between 2 perfect squares is a prime number, so i made a program that does the math for you.
Code:
#include<iostream>
using namespace std;
int counter = 1;
int main()
{
int num1;
do
{
cout << "enter a number: ";
cin >> num1;
int num2 = num1 + 1;
int square1 = num1 * num1;
int square2 = num2 * num2;
int prime = square2 - square1;
cout << "your prime number is: " << prime << endl;
}
while (counter = 1);
cin.get();
return 0;
}
yeah i couldnt get a "yes/no would you like to do it again" thing to work, so i just made it loop like that.
also, dont try to enter a letter, it spazzes out. :confused:
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5^2 = 25
4^2 = 16
25 - 16 = 9, which is not a prime.
I regret to inform you that your theorem doesn't hold, but I genuinely applaud your interest in number theory. I suggest getting a book on the subject or taking a course in it. It's good stuff.
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damnit, i just came to inform you of that, heh. :p
i've been testing it all morning and just decided to work with the small numbers, damn small numbers make me feal stupid :( lol:D
i tested up to getting the answer 65. here are my results. number i put in)number i got(numbers its devisible by
4)9(3
7)15(3,5
10)21(7
12)25(5
17)35(5,7
22)45(5,9-15,3
24)49(7
27)55(5,11
32)65(5,13
it seems that its almost true, except for being devisible by the prime numbers themselves, and - in the of 22, a number previouly gotten.
i still have work. thanks for wasting your time to read that ;)