#include <vector> 
#include <list> 
#include <map> 
#include <set> 
#include <deque> 
#include <queue> 
#include <stack> 
#include <bitset> 
#include <algorithm> 
#include <functional> 
#include <numeric> 
#include <utility> 
#include <sstream> 
#include <iostream> 
#include <iomanip> 
#include <cstdio> 
#include <cmath> 
#include <cstdlib> 
#include <cctype> 
#include <string> 
#include <cstring> 
#include <ctime> 

using namespace std;

#define _int64 long long

double d[1100][1100];
int num[10];

double solve(int x,int y)
{
  double ans;
  if (d[x][y]>-0.5) return d[x][y];
  if (y%2==0)
  {
    ans=x+y;
    if (x>0)
      ans+=(double)x/(x+y)*solve(x-1,y);
    if (y>0)
      ans+=(double)y/(x+y)*solve(x,y-1);
  }
  else
  {
    if (y>0)
      ans=solve(x,y-1);
    else ans=solve(x-1,y);
  }
  d[x][y]=ans;
  return ans;
}

int main()
{
  double ans;
  int i,j,l,t,ans1,n,x;
  for (i=0;i<1100;i++)
    for (j=0;j<1100;j++)
      d[i][j]=-1;
  d[0][0]=0;
  scanf("%d",&t);
  for (l=0;l<t;l++)
  {
    scanf("%d",&n);
    memset(num,0,sizeof(num));
    for (i=0;i<n;i++)
    {
      scanf("%d",&x);
      num[x%2]++;
    }
    ans=solve(num[0],num[1]);
    ans1=(int)(ans*3+0.5);
    printf("%d\n",ans1);
  }
}