program pairs;
type vector=array[1..40000] of longint ;
var v:vector;
    ok:boolean;
    i,ii,a,b,c,r,n,x:longint;
    f,g:text;
begin
assign(f,'pairs.in');
reset(f);
assign(g,'pairs.out');
rewrite(g);
read(f,n);
for i:= 1 to n do
    read(f,v[i]);
x:=0;
for i:= 1 to n do
    for ii := i+1 to n do
    begin
if (v[i]div 2<>0) or (v[ii] div 2<>0) then
begin
a:=v[i];
b:=v[ii];
repeat
r:=a mod b;
a:=b;
b:=r;
until b=0;
if a=1 then
x:=x+1;
end;
end;
write(g,x);
close(f);
close(g);
end.