import bisect
import copy
import decimal
import fractions
import heapq
import itertools
import math
import random
import sys
import time
from collections import Counter,deque,defaultdict
from functools import lru_cache,reduce
from heapq import heappush,heappop,heapify,heappushpop,_heappop_max,_heapify_max
def _heappush_max(heap,item):
    heap.append(item)
    heapq._siftdown_max(heap, 0, len(heap)-1)
def _heappushpop_max(heap, item):
    if heap and item < heap[0]:
        item, heap[0] = heap[0], item
        heapq._siftup_max(heap, 0)
    return item
from math import gcd as GCD
read=sys.stdin.read
readline=sys.stdin.readline
readlines=sys.stdin.readlines
write=sys.stdout.write

def Extended_Euclid(n,m):
    stack=[]
    while m:
        stack.append((n,m))
        n,m=m,n%m
    if n>=0:
        x,y=1,0
    else:
        x,y=-1,0
    for i in range(len(stack)-1,-1,-1):
        n,m=stack[i]
        x,y=y,x-(n//m)*y
    return x,y

class MOD:
    def __init__(self,p,e=None):
        self.p=p
        self.e=e
        if self.e==None:
            self.mod=self.p
        else:
            self.mod=self.p**self.e

    def Pow(self,a,n):
        a%=self.mod
        if n>=0:
            return pow(a,n,self.mod)
        else:
            assert math.gcd(a,self.mod)==1
            x=Extended_Euclid(a,self.mod)[0]
            return pow(x,-n,self.mod)

    def Build_Fact(self,N):
        assert N>=0
        self.factorial=[1]
        if self.e==None:
            for i in range(1,N+1):
                self.factorial.append(self.factorial[-1]*i%self.mod)
        else:
            self.cnt=[0]*(N+1)
            for i in range(1,N+1):
                self.cnt[i]=self.cnt[i-1]
                ii=i
                while ii%self.p==0:
                    ii//=self.p
                    self.cnt[i]+=1
                self.factorial.append(self.factorial[-1]*ii%self.mod)
        self.factorial_inve=[None]*(N+1)
        self.factorial_inve[-1]=self.Pow(self.factorial[-1],-1)
        for i in range(N-1,-1,-1):
            ii=i+1
            while ii%self.p==0:
                ii//=self.p
            self.factorial_inve[i]=(self.factorial_inve[i+1]*ii)%self.mod

    def Fact(self,N):
        if N<0:
            return 0
        retu=self.factorial[N]
        if self.e!=None and self.cnt[N]:
            retu*=pow(self.p,self.cnt[N],self.mod)%self.mod
            retu%=self.mod
        return retu

    def Fact_Inve(self,N):
        if self.e!=None and self.cnt[N]:
            return None
        return self.factorial_inve[N]

    def Comb(self,N,K,divisible_count=False):
        if K==0:
            return 1
        if K<0 or K>N:
            return 0
        retu=self.factorial[N]*self.factorial_inve[K]%self.mod*self.factorial_inve[N-K]%self.mod
        if self.e!=None:
            cnt=self.cnt[N]-self.cnt[N-K]-self.cnt[K]
            if divisible_count:
                return retu,cnt
            else:
                retu*=pow(self.p,cnt,self.mod)
                retu%=self.mod
        return retu

def NTT(polynomial0,polynomial1):
    if mod==998244353:
        prim_root=3
        prim_root_inve=332748118
    else:
        prim_root=Primitive_Root(mod)
        prim_root_inve=MOD(mod).Pow(prim_root,-1)
    def DFT(polynomial,n,inverse=False):
        if inverse:
            for bit in range(1,n+1):
                a=1<<bit-1
                x=pow(prim_root,mod-1>>bit,mod)
                U=[1]
                for _ in range(a):
                    U.append(U[-1]*x%mod)
                for i in range(1<<n-bit):
                    for j in range(a):
                        s=i*2*a+j
                        t=s+a
                        polynomial[s],polynomial[t]=(polynomial[s]+polynomial[t]*U[j])%mod,(polynomial[s]-polynomial[t]*U[j])%mod
            x=pow((mod+1)//2,n,mod)
            for i in range(1<<n):
                polynomial[i]*=x
                polynomial[i]%=mod
        else:
            for bit in range(n,0,-1):
                a=1<<bit-1
                x=pow(prim_root_inve,mod-1>>bit,mod)
                U=[1]
                for _ in range(a):
                    U.append(U[-1]*x%mod)
                for i in range(1<<n-bit):
                    for j in range(a):
                        s=i*2*a+j
                        t=s+a
                        polynomial[s],polynomial[t]=(polynomial[s]+polynomial[t])%mod,U[j]*(polynomial[s]-polynomial[t])%mod

    l=len(polynomial0)+len(polynomial1)-1
    n=(len(polynomial0)+len(polynomial1)-2).bit_length()
    polynomial0=polynomial0+[0]*((1<<n)-len(polynomial0))
    polynomial1=polynomial1+[0]*((1<<n)-len(polynomial1))
    DFT(polynomial0,n)
    DFT(polynomial1,n)
    ntt=[x*y%mod for x,y in zip(polynomial0,polynomial1)]
    DFT(ntt,n,inverse=True)
    ntt=ntt[:l]
    return ntt

def Primitive_Root(p):
    if p==2:
        return 1
    if p==167772161:
        return 3
    if p==469762049:
        return 3
    if p==754974721:
        return 11
    if p==998244353:
        return 3
    if p==10**9+7:
        return 5
    divisors=[2]
    pp=(p-1)//2
    while pp%2==0:
        pp//=2
    for d in range(3,pp+1,2):
        if d**2>pp:
            break
        if pp%d==0:
            divisors.append(d)
            while pp%d==0:
                pp//=d
    if pp>1:
        divisors.append(pp)
    primitive_root=2
    while True:
        for d in divisors:
            if pow(primitive_root,(p-1)//d,p)==1:
                break
        else:
            return primitive_root
        primitive_root+=1

mod=773001541750008261378049
X,Y,Z=map(int,readline().split())
M=10**9+7
MD=MOD(M)
MD.Build_Fact(2*(X+Y+Z))
ans=0
dp=[MD.Comb(X+c-1,X)*MD.Comb(Y+c-1,Y)%M*MD.Comb(Z+c-1,Z)%M*MD.Fact_Inve(c)%M for c in range(X+Y+Z+1)]
f=[MD.Fact_Inve(n)*(-1)**n%M for n in range(X+Y+Z+1)]
f=NTT(f,dp)
for n in range(X+Y+Z+1):
    f[n]%=M
ans=0
for n in range(X+Y+Z+1):
    ans+=f[n]*MD.Fact(n)%M
ans%=M
print(ans)