#include <iostream>

 #include <cstring>

 #include <cmath>

 #define maxn 100010

 using namespace std;

 int sign[maxn];

 int pri[maxn];

 int tot;

 int e;

 int n[],k[];

 void getpri (){

 memset (sign,,sizeof sign);

 tot=;

 sign[]=sign[]=;

 for (int i=;i*i<maxn;i++){

 if (!sign[i]){

 for (int j=i*i;j<maxn;j+=i){

 sign[j]=;

 }

 }

 }

 for (int i=;i<maxn;i++){

 if (!sign[i]){

 pri[tot++]=i;

 }

 }

 }

 int main (){

 long long ans;

 getpri ();

 int t;

 while (cin>>t){

 int minnn=maxn+;

 for (int i=;i<t;i++){

 cin>>n[i]>>k[i];

 minnn=min (minnn,n[i]);

 k[i]=min (k[i],n[i]-k[i]);

 }

 ans=;

 for (int i=;i<tot&&pri[i]<minnn;i++){　　//每次处理单个素因子

 e=;

 int temp=;

 for (int j=;j<t;j++){

 temp=;

 int flag=n[j];

 while (flag){　　//求 n! 中因子 pri(i) 的个数

 temp+=flag/pri[i];

 flag/=pri[i];

 }

 flag=k[j];

 while (flag){

 temp-=flag/pri[i];

 flag/=pri[i];

 }

 flag=n[j]-k[j];

 while (flag){

 temp-=flag/pri[i];

 flag/=pri[i];

 }

 e=min (e,temp);

 }//cout<<e<<pri[i];

 while (e--){

 ans*=pri[i];

 }

 }

 cout<<ans<<endl;

 }

 return ;

 }