Program PascalGuru;
var
k, summa: real;
i, n: integer;
begin
write('n= ');
readln(n);
i := 0;
summa := 0;
repeat
inc(i);
k := (i * i) / (2 + (i * i * i));
summa := summa + k;
until i = n;
writeln('Summa= ', summa:0:2);
readln;
end.