//Date: 2025-02-08 09:39:47
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define P emplace_back
#define CLEAR(a,v) memset(a,(v),sizeof(a))
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define per(i,a,b) for(int i=(a);i>=(b);i--)
//char buf[1<<20],*p1,*p2;
//#define getchar() (p1==p2&&(p2=(p1=buf)+fread(buf,1,1<<20,stdin),p1==p2)?EOF:*p1++)
inline int rd() {
    int s=0,m=0;char ch=getchar();
    while(!isdigit(ch)) {if(ch=='-')m=1;ch=getchar();}
    while( isdigit(ch)) s=(s<<3)+(s<<1)+(ch^48),ch=getchar();
    return m?-s:s;
}
bool MBE;
namespace SOLVER {
#define ldb long double
const int N=4e6,M=1e9+7;const ldb pi=acosl(-1);
int qpow(int x,int y=M-2) {int s=1;for(;y;y>>=1,x=1ll*x*x%M) if(y&1) s=1ll*s*x%M;return s;}
int rv[7000005];
int init(int n) {
    int nn=1,k=0;while(nn<=n) nn<<=1,k++;
    for(int i=0;i<(1<<k);i++) rv[i]=(rv[i>>1]>>1)|((i&1)<<(k-1));return nn;
}
#define cp complex<long double>
void fft(cp f[],int n,int fl) { 
    cp x,y;rep(i,0,n-1) if(i<rv[i]) swap(f[i],f[rv[i]]);
	for(int i=1;i<n;i*=2) {
		cp wi=exp(cp(0,fl*pi/i));for(int j=0;j<n;j+=i*2) 
            {cp w(1,0);for(int k=j;k<i+j;k++,w*=wi) x=f[k],y=w*f[k+i],f[k]=x+y,f[k+i]=x-y;}
	}
	if(fl==-1) rep(i,0,n-1) f[i]/=n;
}
int x,y,z,fac[4000005],ifac[4000005],ans;int C(int n,int m) {return n<m||m<0?0:1ll*fac[n]*ifac[m]%M*ifac[n-m]%M;}
cp a[7000005],b[7000005];
void MAIN() {
    cin>>x>>y>>z;if(!x&&!y&&!z) {puts("1");return;}
    fac[0]=1;rep(i,1,N) fac[i]=1ll*fac[i-1]*i%M;ifac[N]=qpow(fac[N]);per(i,N,1) ifac[i-1]=1ll*ifac[i]*i%M;
    rep(i,0,x+y+z) a[i]={(i%2?M-ifac[i]:ifac[i]),0},b[i]={1ll*C(x+i-1,i-1)*C(y+i-1,i-1)%M*C(z+i-1,i-1)%M*ifac[i]%M,0};
    // rep(i,0,x+y+z) cout<<(int)a[i].real()<<' ';cout<<endl;
    // rep(i,0,x+y+z) cout<<(int)b[i].real()<<' ';cout<<endl;
    // cerr<<a[0].real()<<' '<<b[0]<<endl;
    int nn=init((x+y+z)*2);fft(a,nn,1),fft(b,nn,1);rep(i,0,nn-1) a[i]*=b[i];fft(a,nn,-1);
    // rep(i,0,1) cout<<(int)((__int128)(a[i].real()+0.5)%M)<<' ';
    rep(i,0,x+y+z) ans=(ans+(ll)((__int128)(a[i].real()+0.5)%M)*fac[i])%M;cout<<(ans%M+M)%M<<endl;
}
}
bool MED;
signed main() {
    //freopen(".in","r",stdin);freopen(".out","w",stdout);
    for(int tt=1;tt;tt--) SOLVER::MAIN();
    cerr<<(&MBE-&MED)/1024<<" KB, "<<1000*clock()/CLOCKS_PER_SEC<<" ms\n";
    return 0;
}
//0 1 10369726 466296059 317067586 191166805 623283794 286237724 241389639 965510539 501703982 569244681 214135196 700980621 88649381 86700887 369043724 149929851 735996116 954640431 335463989 177096711