program pairs;



type multime=array[1..100000] of longint;


var m:multime;
    f,g:text;
    n,c,i,ii,a,b,r:longint;

begin
assign (f,'pairs.in');
assign (g,'pairs.out');
reset (f);
rewrite (g);
read (f,n);
for i:=1 to n do
read (f,m[i]);
c:=0;
for i:=1 to n do
for ii:=i+1 to n do
if (m[i] div 2<>0) or (m[ii] div 2<>0) then
   begin
a:=m[i];
b:=m[ii];
repeat
r:= a mod b;
a:=b;
b:=r;
until b=0;
if a=1 then inc(c);
end;

write (g,c);
close (g);
close (f);
end.