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:

Find the sum modulo 1073741824 (2<sup class="upper-index">30</sup>).
The first line contains three space-separated integers *a*, *b* and *c* (1 ≤ *a*, *b*, *c* ≤ 100).
def divisor(n):
    p = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71,73, 79, 83, 89, 97]
    k = 1
    for i in p:
        j = 1
        if n < i:
            break
        while n % i == 0 and n >= i:
            n /= i
            j += 1
        k *= j
    return k
def solve():
    a,b,c=map(int,input().split())
    ans=0
    dic = {}
    for i in range(1,a+1):
        for j in range(1,b+1):
            for k in range(1,c+1):
                l = i*j*k
                if l not in dic:
                    dic[l] = divisor(l)
                ans +=dic[l]
    print(ans%1073741824)
                
if __name__ == '__main__':
    solve()