3 of 8 deleted 79 characters in body

C: 127

n,i,o,c,l;main(){for(scanf("%d",&n),i=3,l=2;o<n;i++){for(c=2;c<=i-1&&i%c;c++);l=c==i?o+=i==l+2,i:l;}printf("%d, %d\n",l-2,l);}

Sample run:

$ for i in $(seq 1 10); do echo $i | ./twinprimes; done
3, 5
5, 7
11, 13
17, 19
29, 31
41, 43
59, 61
71, 73
101, 103
107, 109