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 Mura;
/*****   BY MURAD   ******/
/*Everyone has a different way of thinking, so God Created us*/
/*Hope You Respect My Way..,Thank You*/

import java.io.*;
import java.text.DecimalFormat;
import java.util.*;
import java.util.ArrayList;
import java.util.StringTokenizer;
public class Code {
    public static int []dp=new int[1000001];
    static class DPS {
        void print(int a[][])
        {
            for(int i=0;i<a.length;i++)
            {
                for(int j=0;j<a[0].length;j++)
                {
                    System.out.print(a[i][j]+" ");
                }
                System.out.println();
            }
        }
        int lcs( char[] X, char[] Y, int m, int n )
        {
            int L[][] = new int[m+1][n+1];
            for (int i=0; i<=m; i++)
            {
                for (int j=0; j<=n; j++)
                {
                    if (i == 0 || j == 0) {
                        L[i][j] = 0;
                        continue;
                    }
                    else if (X[i-1] == Y[j-1])
                        L[i][j] = L[i-1][j-1] + 1;
                    else
                        L[i][j] = Math.max(L[i-1][j], L[i][j-1]);
                }
            }
            return L[m][n];
        }
        String LongestSubPlindrome(String s) {
            int len = s.length();
            if (s == null || len < 2)
                return s;
            boolean table[][] = new boolean[len][len];
            int left = 0, right = 0;
            for (int i = 1; i < len; i++) {
                for (int j = 0; j < i; j++) {
                    boolean isplindrome = table[i - 1][j + 1] || i - j <= 2;
                    if (s.charAt(i) == s.charAt(j) && isplindrome) {
                        table[i][j] = true;
                        if (i - j > right - left) {
                            left = j;
                            right = i;
                        }
                    }
                }
            }
            return s.substring(left, right + 1);
        }
        int knp(int []wt,int []val,int n,int W)
        {
            int i, w;
            int K[][] = new int[n+1][W+1];

            // Build table K[][] in bottom up manner
            for (i = 0; i <= n; i++)
            {
                for (w = 0; w <= W; w++)
                {
                    if (i==0 || w==0)
                        K[i][w] = 0;
                    else if (wt[i-1] <= w)
                        K[i][w] = Math.max(val[i-1] + K[i-1][w-wt[i-1]],  K[i-1][w]);
                    else
                        K[i][w] = K[i-1][w];
                }
            }

            return K[n][W];
        }
        int cutRod(int price[],int n)
        {
            int val[] = new int[n+1];
            val[0] = 0;
            // Build the table val[] in bottom up manner and return
            // the last entry from the table
            for (int i = 1; i<=n; i++)
            {
                int max_val = Integer.MIN_VALUE;
                for (int j = 0; j < i; j++)
                    max_val = Math.max(max_val,
                            price[j] + val[i-j-1]);
                val[i] = max_val;
            }
            return val[n];
        }
        int LIS(int []a,int n)
        {
            int dp[]=new int[n+1];
            dp[0]=1;
            for(int i=1;i<n;i++)
            {
                int maxval=Integer.MIN_VALUE;
                for(int j=0;j<i;j++)
                {
                    if(a[i]>a[j])
                    {
                        dp[i]=dp[i-1]+1;
                    }
                    else
                    {
                        dp[i]=dp[i-1];
                    }
                }
            }
            return dp[n-1];
        }
        int edit_dist(char[]x,char[]y,int xl,int yl)
        {
            int dp[][]=new int[xl+1][yl+1];
            for(int i=0;i<=xl;i++)
            {
                for(int j=0;j<=yl;j++)
                {
                    if (i==0) {
                        dp[i][j] = j;
                        continue;
                    }
                    if (j==0) {
                        dp[i][j] = i;
                        continue;
                    }
                    if(x[i-1]==y[j-1])
                    {
                        dp[i][j]=dp[i-1][j-1];
                    }
                    else
                        dp[i][j]=1+Math.min(dp[i][j-1],Math.min(dp[i-1][j],dp[i-1][j-1]));
                }
            }
            return dp[xl][yl];
        }
    }
    static class DC{
        void insertion_sort(int []a,int left,int right)
        {
            int n = left + right;
            for (int i = left + 1; i <= right; ++i)
            {
                int key = a[i];
                int j = i - 1;
                while (j >= 0 && a[j] > key)
                {
                    a[j + 1] = a[j];
                    j = j - 1;
                }
                a[j + 1] = key;
            }
        }

        void merg(int []arr,int low,int mid,int hig)
        {
            int nleft=mid-low+1;
            int nright=hig-mid;
            int left[]=new int[nleft];
            int []right=new int[nright];
            for(int i=0;i<nleft;i++)
                left[i]=arr[i+low];
            for(int j=0;j<nright;j++)
                right[j]=arr[j+mid+1];
            int i=0,j=0;
            int k=low;
            while (i<nleft&&j<nright)
            {
                if(left[i]<=right[j])
                {
                    arr[k]=left[i];
                    i++;
                }
                else
                {
                    arr[k]=right[j];
                    j++;
                }
                k++;
            }
            while(i<nleft)
            {
                arr[k]=left[i];
                i++;
                k++;
            }
            while(j<nright)
            {
                arr[k]=right[j];
                j++;
                k++;
            }
        }
        void sort_merg(int []a,int low,int hig){
            if(low<hig)
            {
                int mid=(low+hig)/2;
                sort_merg(a,low,mid);
                sort_merg(a,mid+1,hig);
                merg(a,low,mid,hig);
            }
        }
        int findKthLargest(int[] nums, int k) {
            int start = 0, end = nums.length - 1, index = nums.length - k;
            while (start < end) {
                int pivot = partion(nums, start, end);
                if (pivot < index) start = pivot + 1;
                else if (pivot > index) end = pivot - 1;
                else return nums[pivot];
            }
            return nums[start];
        }
        int partion(int[] nums, int start, int end) {
            int pivot = start, temp;
            while (start <= end) {
                while (start <= end && nums[start] <= nums[pivot]) {
                    start++;
                }
                while (start <= end && nums[end] > nums[pivot]) {
                    end--;
                }
                if (start > end) break;
                temp = nums[start];
                nums[start] = nums[end];
                nums[end] = temp;
            }
            temp = nums[end];
            nums[end] = nums[pivot];
            nums[pivot] = temp;
            return end;
        }
        int kth_smallest(int a[],int low,int hig,int k)
        {
            if(k<=low+hig)
            {
                int pos=partition_qs(a,low,hig);
                if(pos==k)
                    return a[pos];
                if(pos>k)
                    return kth_smallest(a,low,pos-1,k);
                return kth_smallest(a,pos+1,hig,k);
            }
            return 0;
        }
        int partition_qs(int a[],int low,int hig){
            int i=low-1;
            int j=low;
            int piv=a[hig];
            for(j=low;j<hig;j++)
            {
                if(a[j]<=piv)
                {
                    i++;
                    int temp=a[i];
                    a[i]=a[j];
                    a[j]=temp;
                }
            }
            int temp=a[i+1];
            a[i+1]=piv;
            a[hig]=temp;
            return i+1;
        }
        void sort(int a[],int low,int hig)
        {
            if(low<hig)
            {
                int p1=partition_qs(a,low,hig);
                sort(a,low,p1-1);
                sort(a,p1+1,hig);
            }
        }
    }
    public static long mod=1073741824;
    public static boolean isPowerOfTwo(int n)
    {
        if (n == 0)
            return false;
        while (n != 1)
        {
            if (n % 2 != 0)
                return false;
            n = n / 2;
        }
        return true;
    }
    public static long GCD(long x,long y){
        if(y==0)
            return x;
        else
            return GCD(y,x%y);
    }
    public static int count_number_of_div(int a)
    {
        if(dp[a]!=0)
            return dp[a];
        int c=0;
        int i=1;
        for(i=1;i*i<=a;i++)
        {
            if(a%i==0) {
                c++;
                if (i * i != a)
                    c++;
            }
        }
        dp[a]=c;
        return c;
    }
    static class Graph {
        class Edge {
            int v, w;

            public Edge(int v, int w) {
                this.v = v;
                this.w = w;
            }
        }

        List<Edge> G[];

        public Graph(int n) {
            G = new LinkedList[n];
            for (int i = 0; i < G.length; i++)
                G[i] = new LinkedList<Edge>();
        }

        void addEdge(int u, int v, int w) {
            G[u].add(new Edge(v, w));
            G[v].add(new Edge(u, w));
        }
    }
    public static void main(String[] args)throws IOException {
        Scanner inp = new Scanner(System.in);
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());
        int a=Integer.parseInt(st.nextToken()),b=Integer.parseInt(st.nextToken()),c=Integer.parseInt(st.nextToken());
        long res=0;
        for(int i=1;i<=a;i++)
        {
            for(int j=1;j<=b;j++)
            {
                for(int k=1;k<=c;k++) {

                    res+=count_number_of_div(i*j*k);
                }
            }
        }
        System.out.println(res%mod);
    }
    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.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }
        public int nextInt() {
            return Integer.parseInt(next());
        }
    }
    static class Pair implements Comparable<Pair> {
        double value;
        int idx;
        Pair(double v, int i)
        {
            value = v;
            idx = i;
        }
        @Override
        public int compareTo(Pair p) {
            return (int)(value - p.value);
        }
    }
    public static int[] bctsort(int[] array, int bucketCount) {
        if (bucketCount <= 0) throw new IllegalArgumentException("Invalid bucket count");
        if (array.length <= 1) return array;
        int high = array[0];
        int low = array[0];
        for (int i = 1; i < array.length; i++) {
            if (array[i] > high) high = array[i];

            if (array[i] < low) low = array[i];
        }
        double interval = ((double)(high - low + 1))/bucketCount;
        ArrayList<Integer> buckets[] = new ArrayList[bucketCount];
        for (int i = 0; i < bucketCount; i++) {

            buckets[i] = new ArrayList();

        }
        for (int i = 0; i < array.length; i++) {

            buckets[(int)((array[i] - low)/interval)].add(array[i]);
        }
        int pointer = 0;

        for (int i = 0; i < buckets.length; i++) {

            Collections.sort(buckets[i]);

            for (int j = 0; j < buckets[i].size(); j++) {

                array[pointer] = buckets[i].get(j);

                pointer++;

            }
        }
        return array;
    }
    /*
      int maxValueInMap=(Collections.max(mp.values()));  // This will return max value in the Hashmap
        for (Map.Entry<String, Integer> entry : mp.entrySet()) {  // Itrate through hashmap
            if (entry.getValue()==maxValueInMap) {
                System.out.println(entry.getKey());
                break;
            }
        }
        Relatively Prime :- if diffrence between two number is equal to 1
    */
}