Hi Johannes, Thank you for letting me know and sorry for the trouble! It should be fixed now. Dmitri -- main(i,j){for(i=2;;i++){for(j=2;j<i;j++){if(!(i%j)){j=0;break;}}if (j){printf("%d\n",i);}}} /*Dmitri Gribenko <gribozavr at gmail.com>*/