import java.util.Scanner;
public class P1036{
static int n,k,count=0;
static int[] a ;
static boolean[] flag ;
static int[] b ;
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
n = sc.nextInt();
k = sc.nextInt();
a = new int[n+1];
flag = new boolean[n+1];
b = new int[k+1];
for(int i=1;i<=n;i++) {
a[i] = sc.nextInt();
}
dfs(1,1);
System.out.println(count);
}
private static void dfs(int pos,int starts) {
if(pos==k+1) {
int sum = 0;
for(int j=1;j<=k;j++) {
sum += b[j];
}
if(sum!=0&&isSuShu(sum)) {
count++;
}
return;
}
for(int i=starts;i<=n;i++) {
if(flag[i]==false) {
b[pos] = a[i];
flag[i] = true;
dfs(pos+1,i+1);
flag[i] = false;
}
}
}
/**
* 判断一个数是否为素数
* @param sum
* @return
*/
private static boolean isSuShu(int sum) {
for(int i=2;i<sum/2;i++) {
if(sum%i==0) {
return false;
}
}
return true;
}
}