Goldbach's Other Conjecture
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class Main {
public static void main(String[] args) {
int n = 9;
int x = 2;
int y = 1;
boolean foundWrong = false;
boolean foundTrue = false;
while(foundWrong == false) {
//increasing test number
foundTrue = false;
while(x <= n && foundTrue == false){
//increasing subtracted number
if(isPrime(x)) {
y = n - x;
if(Math.sqrt(y / 2) % 1 == 0 && y != 0) foundTrue = true;
//System.out.println(n + " = " + x + " + " + y + " is twice a square: " + foundTrue);
}
if(x == 2) x += 1;
else x += 2;
}
if(foundTrue == false) {
foundWrong = true;
System.out.println(n);
}
x = 2;
n += 2;
while(isPrime(n) == true) {
n += 2;
}
}
}
public static boolean isPrime(int x) {
int sqrt = (int) Math.sqrt(x);
if(x <= 1) {
return false;
}
else if(x < 4) {
return true;
}
else{
if(x % 2 == 0) {
return false;
}
for(int i = 3; i <= sqrt; i += 2) {
if(x % i == 0) {
return false;
}
}
return true;
}
}
}
Java
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