#include<iostream>
#include<cstdio>
#include<deque>
using namespace std;
typedef long long LL;
int A[30][30]={{0}};
int lcm(int,int);
int gcd(int,int);
void bfs();
deque<pair<int,int> >Q;
int n,Ans=1;
int main()
{int i,j;
	freopen("testz.in","r",stdin);
	freopen("testz.out","w",stdout);
	ios::sync_with_stdio(false);
	cin>>n;
	for(i=0;i<n;i++)
		for(j=0;j<n;j++){
			cin>>A[i][j];
			A[i][j]--;
		}
	bfs();
	cout<<Ans;
	return 0;
}
int gcd(int x,int y)
{
	return y==0?x:gcd(y,x%y);
}
int lcm(int a,int b)
{
    int temp_lcm;
    temp_lcm=a*b/gcd(a, b); //最小公倍数等于两数之积除以最大公约数
    return temp_lcm;
}
void bfs()
{
	
	Q.push_back(make_pair(0,0));
	while(!Q.empty())
	{
		if(Q.front().first==1)
		{
			Ans=lcm(Ans,Q.front().second);
			goto CH;
		}
		for(int i=0;i<n;i++)
			if(A[Q.front().first][i]!=-1)
				Q.push_back(make_pair(i,gcd(Q.front().second,A[Q.front().first][i])));
		CH:;
		Q.pop_front();
	}
}