program MayLava;
var
 q:array[1..20]of longint;
 n,k,sum:longint;
procedure start;
 var
  f:text;
  i:integer;
 begin
  assign(f,'choose.in');
  reset(f);
  readln(f,n,k);
  for i:=1 to n do
   read(f,q[i]);
  close(f);
  sum:=0;
 end;
function check(x:longint):boolean;
 var
  i:integer;
 begin
  for i:=2 to trunc(sqrt(x)) do
   if (x/i)=trunc(x/i) then exit(false);
  exit(true);
 end;
procedure hunt(a,p,x:longint);
 begin
  if p>n then exit;
  if x=k then begin
   if check(a) then inc(sum);
   exit;
  end;
  hunt(a+q[p+1],p+1,x+1);
  hunt(a,p+1,x);
 end;
procedure print;
 var
  f:text;
 begin
  assign(f,'choose.out');
  rewrite(f);
  writeln(f,sum);
  close(f);
 end;
{===============main=================}
BEGIN
 start;
 hunt(0,0,0);
 print;
END.