#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

constexpr int P = 1000000007;

ll powmod(ll n, ll k) {
    ll r = 1, t = n % P;
    for (; k != 0; k /= 2) {
        if (k & 1) r = r * t % P;
        t = t * t % P;
    }
    return r;
}
ll inv(ll n) {
    return powmod(n, P - 2);
}

vector<int> f0, f1;
void init(int n) {
    f0.resize(n + 1);
    f0[0] = 1;
    for (int i = 1; i <= n; i++) {
        f0[i] = (ll)f0[i - 1] * i % P;
    }
    f1.resize(n + 1);
    f1[n] = inv(f0[n]);
    for (int i = n; i > 0; i--) {
        f1[i - 1] = (ll)f1[i] * i % P;
    }
}
ll fact(int k) {
    return f0[k];
}
ll comb(int n, int k) {
    if (n < k || k < 0) return 0;
    return (ll)f0[n] * f1[k] % P * f1[n - k] % P;
}

int main() {
    int a, b, c;
    cin >> a >> b >> c;

    int n = a + b + c;
    init(n);

    ll r = 0;
    for (int j = 1; j <= a; j++) {
        int a1 = a - j;
        int b1 = b - 1;
        int c1 = c;
        int n1 = a1 + b1 + c1;
        ll t = comb(n1, a1) * comb(b1 + c1, b1) % P;
        t = t * ((powmod(2, n1) + P - 1) % P) % P;
        t = t * c1 % P;
        t = t * inv(n1) % P;
        r += t;
        //r += t * 2^n1-1 * c1/n1;
    }

    cout << r % P << endl;

    return 0;
}