一个oracle的算法问题

declare
v_int int;
begin
  for v_i in 2..100 loop
     if v_i = 2 then
        dbms_output.put_line(v_i);
     end if;
     for v_j in 2..(v_i-1) loop
        v_int := mod(v_i,v_j);
        exit when v_int = 0;
        if v_int<>0 and v_j=(v_i-1) then
           dbms_output.put_line(v_i);
        end if;
     end loop;
  end loop;
end;
/