Let's denote d(n) as the number of divisors of a positive integer n. You are given three integers a, b and c. Your task is to calculate the following sum:

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Find the sum modulo 1073741824 (230).

Input

The first line contains three space-separated integers a, b and c (1 ≤ a, b, c ≤ 100).

Output

Print a single integer — the required sum modulo 1073741824 (230).

Examples

Input

2 2 2


Output

20


Input

5 6 7


Output

1520

Note

For the first example.

  * d(1·1·1) = d(1) = 1; 
  * d(1·1·2) = d(2) = 2; 
  * d(1·2·1) = d(2) = 2; 
  * d(1·2·2) = d(4) = 3; 
  * d(2·1·1) = d(2) = 2; 
  * d(2·1·2) = d(4) = 3; 
  * d(2·2·1) = d(4) = 3; 
  * d(2·2·2) = d(8) = 4. 



So the result is 1 + 2 + 2 + 3 + 2 + 3 + 3 + 4 = 20.
import java.util.*;
import java.io.*;

public class Main {
	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

	

	public static void main(String[] args) throws FileNotFoundException {
	 FastReader scan=new FastReader(); 
	 int a=scan.nextInt();
	 int b=scan.nextInt();
	 int c=scan.nextInt();
	 int mod=(1<<30);
	 int temp[]=new int[1001*1000];
	 for(int i=1;i<temp.length;++i){
		 for(int j=1;j*i<temp.length;++j){
			 temp[i*j]++;
		 }
	 }

 int count=0;
 for(int i=1;i<=a;++i){
	 for(int j=1;j<=b;++j){
		 for(int k=1;k<=c;++k){
			 count=(count%mod+temp[i*j*k]%mod)%mod;
		 }
	 }
 }
 System.out.println(count);


	
	 

	
		 }
		 static HashMap<Integer,Integer>H=new HashMap<Integer,Integer>();
		 static int check(int n){
			 if(H.containsKey(n)){
				 return H.get(n);
			 }
			 int  count=1;
			 
			 for(int i=1;i<=n/2;++i){
				 if(n%i==0)++count;
			 }
			 H.put(n,count);
			 return count;
		 }
	 


	
}



