#include
using namespace std;
int main()
{ int t,n,a[101],i,j,f;
cin>>t;
for(i=0;i<t;i++)
{
cin>>n;
for(j=0;j<n;j++)
{cin>>a[j];}
if(a[n/2]==7)
{ for(j=0;j<n/2;j++)
{ if((a[j])!=(a[n-j-1]))
{ f=1;break;}
}
f==0?cout<<"\nyes":cout<<"\nno";
}
else cout<<"\nno";
}
return 0;
}