#!/usr/bin/env python3.8
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
MOD = 10 ** 9 + 7

a, b, c = map(int, read().split())

U = 3 * 10 ** 5 + 10
pow2 = [1] * U
fact = [1] * U
fact_inv = [1] * U
for n in range(1, U):
    pow2[n] = 2 * pow2[n - 1] % MOD
    fact[n] = n * fact[n - 1] % MOD
fact_inv[-1] = pow(fact[-1], MOD - 2, MOD)
for n in range(U - 1, 0, -1):
    fact_inv[n - 1] = n * fact_inv[n] % MOD


def solve(a, b, c):
    a -= 1
    answer = 0
    for n in range(c - 1, a + b + c):
        m = a + b + c - 1 - n
        cnt = fact[n] * fact_inv[c - 1] * fact_inv[n - c + 1] * fact[a + b] * fact_inv[a] * fact_inv[b]
        if a >= m:
            cnt -= fact[n] * fact_inv[b] * fact_inv[a - m] * fact_inv[c - 1]
        if n == 0:
            avg = 1
        else:
            avg = pow2[n] + (pow2[n] - 1) * fact[n - 1] * fact_inv[n] * (c - 1)
        answer += cnt * avg
    return answer % MOD


print(solve(a, b, c))