Program fractionari;
var n,i,j,s:integer;
    f,g:text;
function cmmdc(a,b:integer):integer;
begin
while a<>b do
if a>b then a:=a-b
       else b:=b-a;
cmmdc:=a;
end;
begin
assign(f,'fractii.in');
reset(f);
assign(g,'fractii.out');
rewrite(g);
read(f,n);
s:=0;
for i:=2 to n do begin
for j:=2 to n do begin
if i>j then if (cmmdc(i,j)=1) then inc(s);
if i<j then if (cmmdc(j,i)=1) then inc(s);
end;
end;
s:=s+(2*n-1);
write(g,s);
close(f);
close(g);
end.