#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=900005,M=1e9+7;
int a,b,c,fac[N],fac2[N],inv[N],f[N];
int ksm(int x,int y){
	if (!y)return 1;
	int z=ksm(x,y/2);
	z*=z;z%=M;
	if (y&1)z*=x;
	return z%M;
}
int C(int x,int y){
	if (x<y)return 0;
	return fac[x]*inv[y]%M*inv[x-y]%M;
}
signed main(){
	scanf("%lld%lld%lld",&a,&b,&c);
	fac[0]=inv[0]=fac2[0]=1;
	for (int i=1;i<N;i++)fac[i]=fac[i-1]*i%M,fac2[i]=fac2[i-1]*3%M,inv[i]=ksm(fac[i],M-2);
	a--;
	int now1=0,now2=1,ans=fac2[b+c];
	for (int i=1;i<=b+c;i++){
		now2=(now2*2-C(i-1,b)+M)%M;
		now1=(now1*2+C(i-1,i-c-1))%M;
		(ans+=fac2[b+c-i]*(now2-now1+M)%M*C(a+i,a))%=M;
	}
	printf("%lld\n",ans);
}