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.
//package concept;
 
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.InputStream;
/*
 * Eclipse Photon
 * @uthor masterbios
 * 
 */
public class Main{
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskAA solver = new TaskAA();
        solver.solve(1, in, out);
        out.close();
    }
 
    static class TaskAA {
    	int divisor[] = new int[1000001];
    	final int mod = (int)Math.pow(2,30);
        public void solve(int testNumber, InputReader in, PrintWriter out) {
        	SeivedDivisor(1000001);
//        	for(int i=0;i<=1000000;i++) {
//        		out.println(i+" "+divisor[i]);
//        	}
        	int a = in.nextInt();
        	int b = in.nextInt();
        	int c = in.nextInt();
        	long ans = 0;
        	for(int i=1;i<=a;i++) {
        		for(int j=1;j<=b;j++) {
        			for(int k=1;k<=c;k++) {
        				ans+=(long)divisor[i*j*k]%mod;
//        				System.err.println(divisor[a*b*c]);
        			}ans%=mod;
        		}
        	}
        	out.println(ans);
        }
        public void SeivedDivisor(int n) {
        	for(int i=1;i<n;i++) {
        		for(int j=i;j<n;j+=i) {
        			divisor[j]++;
        		}
        	}
        }
    }
    
    static class InputReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;
 
        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }
 
        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreElements()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }
 
        public int nextInt() {
            return Integer.parseInt(next());
        }
        public long nextLong() {
            return Long.parseLong(next());
        }
        public Double nextDouble() {
        	return Double.parseDouble(next());
        }
        public char nextChar() {
        	return next().charAt(0);
        }
        
    }
}     