program Semiprimes;

var
  currentnumber, temp: longint;
  isprime: boolean;
  infile,outfile:text;
  L,U: longint;
  prime : array[1..78500] of longint;
  x, y: longint;
  numfactors : integer;
  semicounter : longint;

begin
  prime[1]:=2;
  prime[2]:=3;
  prime[3]:=5;
  prime[4]:=7;
  prime[5]:=11;
  currentnumber:=11;
  for x:=6 to 78500 do
    begin
      repeat
        currentnumber:=currentnumber + 2;
        y:=1;
        isprime:=true;
        repeat
          inc(y);
          if currentnumber mod prime[y] = 0 then
            isprime:=false;
        until (isprime=false) or (prime[y] > sqrt(currentnumber));
      until isprime;
      prime[x]:=currentnumber;
    end;
  assign(infile,'DATA11.txt');
  reset(infile);
  assign(outfile,'OUT11.txt');
  rewrite(outfile);
  for x:= 1 to 5 do
    begin
      readln(infile,L);
      readln(infile,U);
      semicounter := 0;
      for currentnumber := L to U do
        begin
          numfactors:=0;
          y:=1;
          temp:=currentnumber;
          while temp > 1 do
            begin
              if temp mod prime[y] = 0 then
                begin
                  temp := temp div prime[y];
                  inc(numfactors);
                  if numfactors > 2 then
                    temp := 0;
                end
              else
                inc(y);
            end;
          if numfactors = 2 then
            inc(semicounter);
        end;
      writeln(outfile,semicounter);
    end;
  close(infile);
  close(outfile);
end.