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).
import os,sys
from io import BytesIO,IOBase
BUFSIZ=8192
class FastIO(IOBase):
    newlines=0
    def __init__(self,file):
        self._fd=file.fileno()
        self.buffer=BytesIO()
        self.writable="n"in file.mode or "r" not in file.mode
        self.write=self.buffer.write if self.writable else None
    def read(self):
        while True:
            b=os.read(self._fd,max(os.fstat(self._fd).st_size,BUFSIZ))
            if not b:
                break
            ptr=self.buffer.tell()
            self.buffer.seek(0,2),self.buffer.write(b),self.buffer.seek(ptr)
        self.newlines=0
        return self.buffer.read()
    def readline(self):
        while self.newlines==0:
            b=os.read(self._fd,max(os.fstat(self._fd).st_size, BUFSIZ))
            self.newlines=b.count(b"\n")+(not b)
            ptr=self.buffer.tell()
            self.buffer.seek(0, 2),self.buffer.write(b),self.buffer.seek(ptr)
        self.newlines-=1
        return self.buffer.readline()
    def flush(self):
        if self.writable:
            os.write(self._fd,self.buffer.getvalue())
            self.buffer.truncate(0),self.buffer.seek(0)
class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer=FastIO(file)
        self.flush=self.buffer.flush
        self.writable=self.buffer.writable
        self.write=lambda s:self.buffer.write(s.encode("ascii"))
        self.read=lambda:self.buffer.read().decode("ascii")
        self.readline=lambda:self.buffer.readline().decode("ascii")
if sys.version_info[0]<3:
    sys.stdin,sys.stdout=FastIO(sys.stdin),FastIO(sys.stdout)
else:
    sys.stdin,sys.stdout=IOWrapper(sys.stdin),IOWrapper(sys.stdout)
input=lambda:sys.stdin.readline().rstrip("\r\n")
import math
a,b,x=map(int,input().split())
d=dict()
primes=[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47]
for t in range(1,10**2+1):
    d[t]=dict()
    for i in primes:
        d[t][i]=0
for t in range(1,10**2+1):
    i=t
    c=0
    while i%2==0:
        c+=1
        i=i//2
    d[t][2]=c
    for j in range(3,int(math.sqrt(t))+1,2):
        c=0
        while i%j==0:
            c+=1
            i=i//j
        d[t][j]=c
    if i>2:
        d[t][i]=1
ans=0
m=1073741824
for i in range(1,a+1):
    for j in range(1,b+1):
        for k in range(1,x+1):
            pro=1
            for y in primes:
                pro=pro*(d[i][y]+d[j][y]+d[k][y]+1)
            ans=(ans+pro)%m
print(ans)
    
        
