import sys

sys.setrecursionlimit(10**6)
int1 = lambda x: int(x)-1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.buffer.readline())
def FI(): return float(sys.stdin.buffer.readline())
def MI(): return map(int, sys.stdin.buffer.readline().split())
def MF(): return map(float, sys.stdin.buffer.readline().split())
def MI1(): return map(int1, sys.stdin.buffer.readline().split())
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def LI1(): return list(map(int1, sys.stdin.buffer.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def BI(): return sys.stdin.buffer.readline().rstrip()
def SI(): return sys.stdin.buffer.readline().rstrip().decode()
dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
inf = 10**16
# md = 998244353
md = 10**9+7

def nHr(hn, hr):
    return nCr(hn+hr-1, hr-1)

def nPr(com_n, com_r):
    if com_n < com_r: return 0
    return fac[com_n]*ifac[com_n-com_r]%md

def nCr(com_n, com_r):
    if com_r < 0: return 0
    if com_n < com_r: return 0
    return fac[com_n]*ifac[com_r]%md*ifac[com_n-com_r]%md

# 準備
n_max = 300005
fac = [1]
for i in range(1, n_max+1): fac.append(fac[-1]*i%md)
ifac = [1]*(n_max+1)
ifac[n_max] = pow(fac[n_max], md-2, md)
for i in range(n_max-1, 1, -1): ifac[i] = ifac[i+1]*(i+1)%md

a,b,c=MI()
n=a+b+c

pw=[1]
for _ in range(n):pw.append(pw[-1]*2%md)

ans=0
ab=0
for l in range(2,a+b+1):
    r=n-1-l
    ab=(ab+nCr(a+b-l,b-1))%md
    way=nCr(r,c-1)*ab%md
    ev=((c-1)*(pw[r]-1)*pow(r,md-2,md)+pw[r])%md
    ans=(ans+way*ev%md)%md
    # print(ab,way,ev,ans)

print(ans)