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.IOException;
import java.io.OutputStreamWriter;
import java.util.Arrays;
import java.math.BigDecimal;
import java.io.BufferedWriter;
import java.util.Locale;
import java.util.InputMismatchException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.Writer;
import java.math.BigInteger;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 * @author Jacob Jiang
 */
public class Main {
	public static void main(String[] args) {
		InputStream inputStream = System.in;
		OutputStream outputStream = System.out;
		InputReader in = new InputReader(inputStream);
		OutputWriter out = new OutputWriter(outputStream);
		TaskB solver = new TaskB();
		solver.solve(1, in, out);
		out.close();
	}
}

class TaskB {
	public void solve(int testNumber, InputReader in, OutputWriter out) {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();
        int n = a * b * c;
        int[] d = new int[n + 1];
        int[] leastFactor = NumberUtils.generateLeastFactor(n);
        d[1] = 1;
        for (int i = 2; i <= n; i++) {
            int num = i;
            int count = 1;
            while (num % leastFactor[i] == 0) {
                num /= leastFactor[i];
                count++;
            }
            d[i] = d[num] * count;
        }
        int answer = 0;
        for (int i = 1; i <= a; i++) {
            for (int j = 1; j <= b; j++) {
                for (int k = 1; k <= c; k++) {
                    answer += d[i * j * k];
                }
            }
        }
        out.println(answer & ((1 << 30) - 1));
    }
}

class InputReader {

    private InputStream stream;
    private byte[] buf = new byte[1 << 16];
    private int curChar;
    private int numChars;

    public InputReader(InputStream stream) {
        this.stream = stream;
    }

    public int read() {
        if (numChars == -1)
            throw new InputMismatchException();
        if (curChar >= numChars) {
            curChar = 0;
            try {
                numChars = stream.read(buf);
            } catch (IOException e) {
                throw new InputMismatchException();
            }
            if (numChars <= 0)
                return -1;
        }
        return buf[curChar++];
    }

    public int nextInt() {
        int c = read();
        while (isSpaceChar(c))
            c = read();
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        int res = 0;
        do {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res *= 10;
            res += c & 15;
            c = read();
        } while (!isSpaceChar(c));
        return res * sgn;
    }

    public static boolean isSpaceChar(int c) {
        return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }

    }

class OutputWriter {
    private PrintWriter writer;

    public OutputWriter(OutputStream stream) {
        writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(stream)));
    }

    public OutputWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void println(int x) {
        writer.println(x);
    }

    public void close() {
        writer.close();
    }

    }

class NumberUtils {

    public static int[] generateLeastFactor(int num) {
        if (num < 0) throw new IllegalArgumentException();
        if (num == 1) return new int[]{0, 1};
        int[] result = new int[num + 1];
        result[0] = 0;
        result[1] = 1;
        for (int i = 2; i * i <= num; i++) {
            if (result[i] == 0) {
                result[i] = i;
                for (int j = i * i; j <= num; j += i) {
                    if (result[j] == 0) result[j] = i;
                }
            }
        }
        for (int i = 2; i <= num; i++)
            if (result[i] == 0)
                result[i] = i;
        return result;
    }

    }

