local t = io.read("*n")

local function dotask()
  local n = io.read("*n")
  local l = {}
  for i = 1, n do
    local tmp = io.read("*n")
    if(l[tmp] == nil) then l[tmp] = 1 else l[tmp] = l[tmp] + 1 end
  end
  local mcnt = 0
  for k, v in pairs(l) do
    mcnt = math.max(mcnt, v)
  end
  local c = {}
  for i = 1, mcnt do c[i] = 0 end
  local remall = 0
  for k, v in pairs(l) do
    c[v] = c[v] + 1
    remall = remall + 1
  end
  local ret = 0
  while(3 <= remall) do
    if(3 <= c[mcnt]) then
      local num = math.floor(c[mcnt] / 3)
      ret = ret + num
      c[mcnt] = c[mcnt] - 3 * num
      if(1 < mcnt) then
        c[mcnt - 1] = c[mcnt - 1] + 3 * num
      else
        remall = remall - 3 * num
      end
      if(c[mcnt] == 0) then mcnt = mcnt - 1 end
    elseif(2 == c[mcnt]) then
      ret = ret + 1
      c[mcnt] = 0
      for i = mcnt - 1, 1, -1 do
        if(0 < c[i]) then
          c[i] = c[i] - 1
          if(1 < i) then
            c[i - 1] = c[i - 1] + 1
          else
            remall = remall - 1
          end
          break
        end
      end
      c[mcnt - 1] = c[mcnt - 1] + 2
      mcnt = mcnt - 1
    else
      ret = ret + 1
      c[mcnt] = 0
      for i = mcnt - 1, 1, -1 do
        if(2 <= c[i]) then
          c[i] = c[i] - 2
          if(1 < i) then
            c[i - 1] = c[i - 1] + 2
          else
            remall = remall - 2
          end
          break
        elseif(c[i] == 1) then
          c[i] = c[i] - 1
          for j = i - 1, 1, -1 do
            if(0 < c[j]) then
              c[j] = c[j] - 1
              if(1 < j) then
                c[j - 1] = c[j - 1] + 1
              else
                remall = remall - 1
              end
              break
            end
          end
          c[i - 1] = c[i - 1] + 1
          break
        end
      end
      c[mcnt - 1] = c[mcnt - 1] + 1
      mcnt = mcnt - 1
    end
  end
  return ret
end

for i = 1, t do
  print(dotask())
end