# Thread: finding first n semi-prime integers

1. ## finding first n semi-prime integers

HI, i am trying to find the first 2000,000 square free semi-prime numbers( mathWorld , oeis). I have generated the prime numbers but to get these semi-prime numbers i am trying as follows:

Code:
int limit1 = 1000;
int limit2 = 2000;
for(i=0;i<=limit1;i++)
{
for(j=i+1;j<=limit2;j++)
{
semiPrimes[size++]=(primes[i]*primes[j]);
}
limit2++;
}
however on chaging either limit1 or limit2 gives different values for semiprime[200000] . So what should be correct values of these variables?
Thanks.

2. ## Re: finding first n semi-prime integers

Your list is not in order.

You will get 6,10,14,22,26,..............,15,21,33,39,......... ...........35,55,65.......etc

3. ## Re: finding first n semi-prime integers

Originally Posted by a tutor
Your list is not in order.

You will get 6,10,14,22,26,..............,15,21,33,39,......... ...........35,55,65.......etc
that i am managing by sorting the semiPrime array after going out of both loops