program fractii;
uses crt;
var f:text;
    i,j,nr,n:longint;
begin
     assign(f,'fractii.in');
     reset(f);
     readln(f,n);
     close(f);
     assign(f,'fractii.out');
     rewrite(f);
     nr:=1;
     for i:=1 to n do
         for j:=1 to n do
           begin
if (j>i)and((((j mod 2<>0)and(i mod 2=0))or((j mod 2=0)and(i mod 2<>0))or((j mod 2=i mod 2)and(j/i<>0)))or(i=1))then
                        nr:=nr+1;
if (i>j)and((((j mod 2<>0)and(i mod 2=0))or((j mod 2=0)and(i mod 2<>0))or((i/2=j/2)and(i/j<>0)))or(j=1))then
                   nr:=nr+1;
           end;
     writeln(f,nr);
     close(f);
end.