type vector=array[1..669]of integer;
const prime:vector=(2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,
197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,383,389,397,401,409,419,421,431,433,439,443,449,
457,461,463,467,479,487,491,499,503,509,521,523,541,547,557,563,569,571,577,587,593,599,601,607,613,617,619,631,641,643,647,653,659,661,673,677,683,691,701,709,719,727,733,
739,743,751,757,761,769,773,787,797,809,811,821,823,827,829,839,853,857,859,863,877,881,883,887,907,911,919,929,937,941,947,953,967,971,977,983,991,997,1009,1013,1019,1021,
1031,1033,1039,1049,1051,1061,1063,1069,1087,1091,1093,1097,1103,1109,1117,1123,1129,1151,1153,1163,1171,1181,1187,1193,1201,1213,1217,1223,1229,1231,1237,1249,1259,1277,1279,1283,1289,1291,1297,1301,
1303,1307,1319,1321,1327,1361,1367,1373,1381,1399,1409,1423,1427,1429,1433,1439,1447,1451,1453,1459,1471,1481,1483,1487,1489,1493,1499,1511,1523,1531,1543,1549,1553,1559,1567,1571,1579,1583,1597,1601,
1607,1609,1613,1619,1621,1627,1637,1657,1663,1667,1669,1693,1697,1699,1709,1721,1723,1733,1741,1747,1753,1759,1777,1783,1787,1789,1801,1811,1823,1831,1847,1861,1867,1871,1873,1877,1879,
1889,1901,1907,1913,1931,1933,1949,1951,1973,1979,1987,1993,1997,1999,2003,2011,2017,2027,2029,2039,2053,2063,2069,2081,2083,2087,2089,2099,2111,2113,2129,2131,2137,2141,2143,2153,2161,2179,
2203,2207,2213,2221,2237,2239,2243,2251,2267,2269,2273,2281,2287,2293,2297,2309,2311,2333,2339,2341,2347,2351,2357,2371,2377,2381,2383,2389,2393,2399,2411,2417,2423,2437,2441,2447,2459,2467,2473,
2477,2503,2521,2531,2539,2543,2549,2551,2557,2579,2591,2593,2609,2617,2621,2633,2647,2657,2659,2663,2671,2677,2683,2687,2689,2693,2699,2707,2711,2713,2719,2729,2731,2741,2749,2753,2767,
2777,2789,2791,2797,2801,2803,2819,2833,2837,2843,2851,2857,2861,2879,2887,2897,2903,2909,2917,2927,2939,2953,2957,2963,2969,2971,2999,3001,
3011,3019,3023,3037,3041,3049,3061,3067,3079,3083,3089,3109,3119,3121,3137,3163,3167,3169,3181,3187,3191,3203,3209,3217,3221,3229,3251,3253,3257,
3259,3271,3299,3301,3307,3313,3319,3323,3329,3331,3343,3347,3359,3361,3371,3373,3389,3391,3407,3413,3433,3449,3457,3461,3463,3467,3469,3491,3499,3511,
3517,3527,3529,3533,3539,3541,3547,3557,3559,3571,3581,3583,3593,3607,3613,3617,3623,3631,3637,3643,3659,3671,3673,3677,3691,3697,3701,3709,3719,3727,
3733,3739,3761,3767,3769,3779,3793,3797,3803,3821,3823,3833,3847,3851,3853,3863,3877,3881,3889,3907,3911,3917,3919,3923,3929,3931,3943,3947,3967,3989,
4001,4003,4007,4013,4019,4021,4027,4049,4051,4057,4073,4079,4091,4093,4099,4111,4127,4129,4133,4139,4153,4157,4159,4177,4201,4211,4217,4219,4229,4231,4241,
4243,4253,4259,4261,4271,4273,4283,4289,4297,4327,4337,4339,4349,4357,4363,4373,4391,4397,4409,4421,4423,4441,4447,4451,4457,4463,4481,4483,4493,4507,4513,
4517,4519,4523,4547,4549,4561,4567,4583,4591,4597,4603,4621,4637,4639,4643,4649,4651,4657,4663,4673,4679,4691,4703,4721,4723,4729,4733,4751,4759,4783,4787,
4789,4793,4799,4801,4813,4817,4831,4861,4871,4877,4889,4903,4909,4919,4931,4933,4937,4943,4951,4957,4967,4969,4973,4987,4993,4999);
var fi,fo:text;
    i,n,x,j:longint;
    rez,ct,max,nr_div:int64;
    nr1:array[1..1000100]of byte;
    m:array[1..1000100]of longint;
function cauta(nr:longint):boolean;
var st,dr,mij:longint;
begin
  st:=1; dr:=6690; cauta:=false;
  while st<=dr do
    begin
      mij:=(st + dr) shr 1;
      if prime[mij]=nr then begin cauta:=true; exit; end
        else
          if prime[mij]>nr then dr:=mij-1
            else st:=mij+1;
    end;
end;
function prim(nr:longint):boolean;
var i,vari,k:longint;
begin
  nr_div:=0; prim:=true; vari:=nr; ct:=1;
  if cauta(nr)=true then exit;
  for k:=2 to trunc(sqrt(nr)) do
   if vari<>0 then
    begin
     if vari mod (k*k)=0 then begin ct:=2; prim:=false; exit; end;
     if vari mod k=0 then
       begin
       if (vari div k <> 2)and((vari div k) and 1 = 1) then
        if cauta(vari div k)=true then
          begin
            inc(nr_div,2);
            prim:=false;
            exit; end;
        inc(nr_div);
        vari:=vari div k; end;
    end
   else break;
  if nr_div>0 then prim:=false;
end;
procedure verif(i:longint);
var ok:boolean;
begin
  ok:=prim(i);
  if ok=true then rez:=rez+(m[i]*(m[i]-1) shr 1)
    else
      if (nr_div>0)and(ct=1) then
        if nr_div and 1 = 1 then rez:=rez+(m[i]*(m[i]-1) shr 1)
                            else rez:=rez-(m[i]*(m[i]-1) shr 1);
end;
begin
  assign(fi,'pairs.in'); reset(fi);
  assign(fo,'pairs.out'); rewrite(fo);
  readln(fi,n);
  max:=-maxint;
  rez:=0;
  for i:=1 to n do
    begin
      readln(fi,x);
      nr1[x]:=1;
      if x>max then max:=x; end;
  for i:=2 to max do
    begin
      for j:=1 to max div i do
         if nr1[i*j]=1 then inc(m[i]);
      if (m[i]>0) then verif(i);
    end;
  rez:=n*(n-1) shr 1 - rez;
  writeln(fo,rez);
  close(fi);
  close(fo);
end.