#include<bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define int long long
typedef pair<int,int> pii;
typedef vector<pii> vii;
typedef vector<int> vi;
typedef vector<bool> vb;
#define FOR(i,a) for(int i=0;i<(a);i++)
#define FORE(i,a,b) for(int i=(a);i<(b);i++)
#define all(x) x.begin(),x.end()
#define fi first
#define se second
#define pb push_back
#define sp <<" "<<
#define cont(x) for(auto el:x) cout<<el<<' ';cout<<endl;
#define contp(x) for(auto el:x) cout<<el.fi<<'-'<<el.se<<' ';cout<<endl;
#define DEBUG(x) cout<<#x sp x<<endl;
#define carp(x,y) ((x%MOD)*(y%MOD))%MOD
#define topla(x,y) ((x%MOD)+(y%MOD))%MOD
#define mid (l+r)/2
const int MAXN=1e3+5;
const int INF=1e18;
const int MOD=1e9+7;
int fac[MAXN];
int exp(int x,int us){
int res=1;
while(us>0){
if(us&1) res=carp(res,x);
x=carp(x,x);
us/=2;
}
return res;
}
void calc(){
fac[0]=fac[1]=1;
FORE(i,2,MAXN) fac[i]=carp(fac[i-1],i);
}
int inv(int x){
return exp(x,MOD-2);
}
int comb(int n,int r){
if(n<r) return 0;
return carp(fac[n],carp(inv(fac[n-r]),inv(fac[r])));
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
calc();
int n;
cin>>n;
vii a(n+1);
FORE(i,1,n+1) cin>>a[i].fi>>a[i].se;
int pay=0;
FORE(i,1,n+1){
int deg=carp(comb(n,i),i);
pay=topla(pay,deg);
}
cout<<pay<<endl;
}
