import java.util.*;
import java.lang.*;
import java.io.*;

// The main method must be in a class named "Main".
class Main {
    public static boolean isPrime(int n)
    {
        int count=0;
        for(int i=1;i<=Math.sqrt(n);i++){
            if(n%i==0){
                count++;
                if(i!=n/i){
                    count++;
                }
            }
        }
        if(count==2){
            return true;
        }
        return false;
    }
    public static void main(String[] args) {
       Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        int k=sc.nextInt();
        int[] arr=new int[n];
        for(int i=0;i<n;i++){
            arr[i]=sc.nextInt();
        }
       int sum=0;
        for(int i=1;i<n;i++){
            if(isPrime(i+1)){
                System.out.println(arr[i]);
                if(arr[i]>=k){
                    sum+=k;
                }
            }
        }
        System.out.println(sum);
        
    }
}