#include <stdio.h>
int main(void) {
int a[33];
int n=0,i,count,sum=0;
a[0]=2;
a[1]=-1;
while(n<=30){
a[n+2]=-a[n+1]+a[n]+2;
n++;
}
for(n=0;n<=32;n++){
sum=0;
if(a[n]>0){
for(i=1;i<=a[n];i++){
if(a[n]%i==0){
sum++;
}
}
if(sum==2){
count++;
}
}
}
return 0;
}
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