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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.StringTokenizer;


public class CF236B {
	static int N = 1000000;
	static boolean[] isPrime;
	static int mod = 1073741824;
	public static void main(String[] args) throws IOException {
		MyScanner sc = new MyScanner(System.in);
		numDivs(N);
		int a = sc.nextInt(), b = sc.nextInt(), c = sc.nextInt();
		int out = 0;
		for (int i = 1; i <= a; i++) {
			for (int j = 1; j <= b; j++) {
				for (int k = 1; k <= c; k++) {
					out = (out % mod + numDivs[i*j*k] % mod) % mod;
				}
			}
		}
		System.out.println(out);
	}
	
	static int[] numDivs;
	static void numDivs(int n){
		isPrime = new boolean[n+1];
		numDivs = new int[n+1];
		Arrays.fill(isPrime, true);
		Arrays.fill(numDivs, 1);
		isPrime[0] = isPrime[1] = false;
		for (int i = 2; i <= n; i++) {
			if(isPrime[i]){
				numDivs[i]++;
				for (int j = i*2; j <= n; j+=i) {
					isPrime[j] = false;
					int jj = j;
					int c = 1;
					while(jj % i == 0){
						jj/=i;
						c++;
					}
					numDivs[j]*=c;
				}
			}
		}
	}
	static class MyScanner 
	{
		StringTokenizer st;
		BufferedReader br;

		public MyScanner(InputStream s){	br = new BufferedReader(new InputStreamReader(s));}

		public String next() throws IOException 
		{
			while (st == null || !st.hasMoreTokens()) 
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}

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

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

		public String nextLine() throws IOException {return br.readLine();}

		public double nextDouble() throws IOException
		{
			String x = next();
			StringBuilder sb = new StringBuilder("0");
			double res = 0, f = 1;
			boolean dec = false, neg = false;
			int start = 0;
			if(x.charAt(0) == '-')
			{
				neg = true;
				start++;
			}
			for(int i = start; i < x.length(); i++)
				if(x.charAt(i) == '.')
				{
					res = Long.parseLong(sb.toString());
					sb = new StringBuilder("0");
					dec = true;
				}
				else
				{
					sb.append(x.charAt(i));
					if(dec)
						f *= 10;
				}
			res += Long.parseLong(sb.toString()) / f;
			return res * (neg?-1:1);
		}

		public boolean ready() throws IOException {return br.ready();}

	}
}
