nested for loop problem

Would someone be able to tell me why this isn't working. The nested
for loops seem correctly coded to me. I would appreciate any input.

#include <iostream.h>
#include <math.h>

int main ()
{
	int a, b, c, d;

	cout << "Enter two integers ";
		cin >> a >> b;

	for (c=a; c==b; c++)
	{
		for(d=2; d<=sqrt(c); d++)
		{
			if(c%d==0)
				continue;

			else cout << c;
		}
	}
	cout << " are the prime numbers in the range " << a << " to " << b <<
endl;

	return 0;
}