#include<bits/stdc++.h>
using namespace std;

#define int long long

#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,a,b) for(int i=(a);i<(b);i++)
#define pb push_back
#define eb emplace_back
#define all(v) (v).begin(),(v).end()
#define fi first
#define se second

using vint=vector<int>;
using pint=pair<int,int>;
using vpint=vector<pint>;

template<typename A,typename B>inline void chmin(A &a,B b){if(a>b)a=b;}
template<typename A,typename B>inline void chmax(A &a,B b){if(a<b)a=b;}

template<class A,class B>
ostream& operator<<(ostream& ost,const pair<A,B>&p){
    ost<<"{"<<p.first<<","<<p.second<<"}";
    return ost;
}

template<class T>
ostream& operator<<(ostream& ost,const vector<T>&v){
    ost<<"{";
    for(int i=0;i<v.size();i++){
        if(i)ost<<",";
        ost<<v[i];
    }
    ost<<"}";
    return ost;
}

template<uint32_t mod>
struct ModInt{
    uint32_t a;
    ModInt& s(uint32_t vv){
        a=vv<mod?vv:vv-mod;
        return *this;
    }

    ModInt(int64_t x=0){s(x%mod+mod);}

    ModInt& operator+=(const ModInt &x){return s(a+x.a);}
    ModInt& operator-=(const ModInt &x){return s(a+mod-x.a);}
    ModInt& operator*=(const ModInt &x){
        a=uint64_t(a)*x.a%mod;
        return *this;
    }
    ModInt& operator/=(const ModInt &x){
        *this*=x.inv();
        return *this;
    }

    ModInt operator+(const ModInt &x)const{return ModInt(*this)+=x;}
    ModInt operator-(const ModInt &x)const{return ModInt(*this)-=x;}
    ModInt operator*(const ModInt &x)const{return ModInt(*this)*=x;}
    ModInt operator/(const ModInt &x)const{return ModInt(*this)/=x;}
    bool operator==(const ModInt &x)const{return a==x.a;}
    bool operator!=(const ModInt &x)const{return a!=x.a;}
    bool operator<(const ModInt &x)const{return a<x.a;}

    ModInt operator-()const{return ModInt()-*this;}
    ModInt pow(int64_t n)const{
        ModInt res(1),x(*this);
        while(n){
            if(n&1)res*=x;
            x*=x;
            n>>=1;
        }
        return res;
    }

    ModInt inv()const{return pow(mod-2);}
};

template<uint32_t mod>
istream& operator>>(istream& in,const ModInt<mod>& a){
    return (in>>a.a);
}
template<uint32_t mod>
ostream& operator<<(ostream& out,const ModInt<mod>& a){
    return (out<<a.a);
}
using mint=ModInt<1000000007>;

template<class Mint,int32_t lg>
struct ModIntTable{
    int N;
    vector<Mint>facts,finvs,invs;
    ModIntTable():N(1<<lg),facts(N),finvs(N),invs(N){
        const uint32_t mod=Mint(-1).a+1;
        invs[1]=1;
        for(int i=2;i<N;i++)invs[i]=invs[mod%i]*(mod-mod/i);

        facts[0]=1;
        finvs[0]=1;
        for(int i=1;i<N;i++){
            facts[i]=facts[i-1]*i;
            finvs[i]=finvs[i-1]*invs[i];
        }
    }
    inline Mint fact(int n)const{return facts[n];}
    inline Mint finv(int n)const{return finvs[n];}
    inline Mint inv(int n)const{return invs[n];}
    inline Mint binom(int n,int k)const{return facts[n]*finvs[k]*finvs[n-k];}
    inline Mint perm(int n,int k)const{return facts[n]*finvs[n-k];} 
};
ModIntTable<mint,21>mtable;

using Cd = complex<double>;
namespace std {
  template<>
  Cd& Cd::operator*=(const Cd& y) {
    double a = this->real();
    double b = this->imag();
    double c = y.real();
    double d = y.imag();
    return *this=Cd(a*c-b*d, a*d+b*c);
  }
}

template<class Mint,class C>
struct ArbitraryModConvolution15{
    static constexpr double PI=acos(-1);

    static void dft(vector<C>&f){
        int n=f.size();
		int s=__lg(n);

		static vector<vector<C>>w(30);
		w[0]=vector<C>(1,C(1.0,0.0));
		for(int i=1;i<=s;i++){
			if(w[i].size())continue;
			w[i]=vector<C>(1<<i);
			const double t=2*PI/(1<<i);
			for(int j=0;j<1<<i;j++)w[i][j]=(j&1)?polar(1.0,j*t):w[i-1][j>>1];
		}
		

        for(int i=0,j=1;j<n-1;j++){
            for(int k=n>>1;k>(i^=k);k>>=1);
            if(i>j)swap(f[i],f[j]);
        }

		for(int m=1;m<=s;m++){
			for(int i=0;i<n;i+=1<<m){
				for(int j=0;j<1<<m-1;j++){
					C f0=f[i+j],f1=w[m][j]*f[i+j+(1<<m-1)];
					f[i+j]=f0+f1;
					f[i+j+(1<<m-1)]=f0-f1;
				}
			}
		}
	}
	static void idft(vector<C>&f){
		dft(f);
		reverse(f.begin()+1,f.end());
		double in=1.0/f.size();
		for(int i=0;i<f.size();i++)f[i]*=in;
	}

	static vector<Mint>convolute(vector<Mint>A,vector<Mint>B){
		int n=1<<__lg(A.size()+B.size()-2)+1;
        vector<C>g(n),h(n);
		for(int i=0;i<A.size();i++)g[i]=C(A[i].a&~(~0<<15),A[i].a>>15);
		for(int i=0;i<B.size();i++)h[i]=C(B[i].a&~(~0<<15),B[i].a>>15);
		
		dft(g);
		dft(h);

		vector<C>gc=g;
		reverse(gc.begin()+1,gc.end());
		
		C I(0,1);
		for(int i=0;i<n;i++){
			gc[i]=conj(gc[i]);

			C a=(g[i]+gc[i])*h[i]*0.5;
			C b=(g[i]-gc[i])*h[i]*I*(-0.5);
			g[i]=a;h[i]=b;
		}

		idft(g);
		idft(h);
		vector<Mint>AB(A.size()+B.size()-1);
		for(int i=0;i<AB.size();i++){
			Mint ll=g[i].real()+0.5;
			Mint lh=g[i].imag()+0.5;
			Mint hl=h[i].real()+0.5;
			Mint hh=h[i].imag()+0.5;
			AB[i]=(hh*(1<<15)+(lh+hl))*(1<<15)+ll;
		}
		return AB;
	}
};
using FFT=ArbitraryModConvolution15<mint,complex<double>>;
mint po[2222222];
signed main(){
    po[0]=1;
    for(int i=1;i<2222222;i++)po[i]=po[i-1]*2;

    int X,Y,Z;
    cin>>X>>Y>>Z;
    if(X==0&&Y==0&&Z==0){
        cout<<0<<endl;
        return 0;
    }

    vector<mint>F(X+Y+1);
    for(int i=0;i<=X+Y;i++){
        if(i+Z<X||i+Z<Y)continue;
        F[i]=mtable.binom(i+Z,X)*mtable.binom(i+Z,Y)*mtable.binom(i+Z,Z)*mtable.finv(i+Z);
        if((i+Z)&1)F[i]*=-1;
    }

    vector<mint>U(X+Y+1);
    for(int i=0;i<=X+Y;i++)U[i]=mtable.finv(i);

    auto P=FFT::convolute(F,U);
    mint ans=0;
    for(int i=0;i<=X+Y;i++){
        int k=i+Z;
        mint tmp=po[k]*mtable.fact(k)*P[i];
        ans+=tmp;
    }

    ans/=2;
    if(X&1)ans*=-1;
    if(Y&1)ans*=-1;
    if(Z&1)ans*=-1;
    cout<<ans<<endl;
    return 0;
}