{Gigel cand isi facea temele la matematica s-a apucat sa scrie pe o
foaie la matematica un sir de fractii ireductibile de forma P/Q cu 1
mai mic decat P si Q mai mic decat N unde N este un numar natural
ales de el. De exemplu pentru N=4 a obtinu sirul 1/1 1/2 1/3 1/4
2/1 2/3 3/1 3/2 3/4 4/1 4/3}
var n,i,s:longint;
    f,g:text;
function mult(k:longint):longint;
var j,m,h:longint;
begin
m:=0;
for j:=2 to n do if (k mod j=0) or (j mod k=0) then m:=m+1
                 else if ((k-j)>1) and (j mod (k-j)=0) then m:=m+1
                      else if ((j-k)>1) and (k mod (j-k)=0) then m:=m+1;
mult:=m;
end;
function prim(p:longint):boolean;
var d:longint;
    ok:boolean;
begin
ok:=true;
for d:=2 to trunc(sqrt(p)) do if(p mod d=0) then ok:=false;
prim:=ok;
end;
begin
assign(f,'fractii.in');
assign(g,'fractii.out');
reset(f);
rewrite(g);
readln(f,n);
s:=n;
s:=s+n-(n div 2);
for i:=3 to n do s:=s+n-mult(i);
write(g,s);
close(f);
close(g);
end.