14pr4.pas

const
ACC = 10.e-7;
TRM = 10.e+3;
var
   n          : cardinal;
   x, step, s : double;

begin
   n := 1;
   s := 0;
   write('x =');
   readln(x);
   step := 1/x;
   while (step > ACC) AND (n < TRM) do begin
      s += step;
      step := step/((4*x*x)*(2*n + 1)/(2*n - 1));
      n += 1;
   end;
   writeln('s =', s:8:6)
end.