program choose;

type sz=array[1..20]of longint;

var i,n,k:1..20;
    x:sz;
    ans:longint;
    f1:text;

function zhs(n:longint):boolean;
 var i:longint;
 begin
  zhs:=true;
  for i:=2 to trunc(sqrt(n)) do
   if n mod i=0 then
   begin
    zhs:=false;
    break;
   end;
 end;

procedure cho(jl,k:byte; shuzu:sz; he:longint);
 var kb,i:1..20;
     sum:longint;
 begin
  for i:=jl+1 to n do
  begin
   kb:=k;
   sum:=he;
   sum:=sum+shuzu[i];
   kb:=kb-1;
   if kb>0 then cho(i,kb,shuzu,sum) else
   begin
    if zhs(sum) then ans:=ans+1;
   end;
  end;
 end;

begin
 assign(f1,'choose.in');
 reset(f1);

 readln(f1,n,k);
 for i:=1 to n do
  read(f1,x[i]);

 close(f1);

 cho(0,k,x,0);

 assign(f1,'choose.out');
 rewrite(f1);
 writeln(f1,ans);
 close(f1);
end.