# Kept libraries:
# - faster_prime
# Expanded libraries:
# - nanacl/bsearch_right
# Errored libraries:
#   (none)
# Removed libraries:
#   (none)
#
# ------------------------------------------------------------------------------

# frozen_string_literal: true
# This file is expanded by nanacl.

main = -> do # =================================================================
require "faster_prime"
# require "nanacl/bsearch_right" # (expanded: L22)

in_t = gets.chomp.to_i

twin_prime_multiples = []
primes = FasterPrime.each(10**7).to_a
primes.each_cons(2) { |p1, p2| twin_prime_multiples << p1 * p2 if p2 - p1 == 2 }

in_t.times do
  in_n = gets.chomp.to_i
  puts (twin_prime_multiples.bsearch_right { _1 <= in_n } || -1)
end

end # --------------------------------------------------------------------------

# === dependencies -------------------------------------------------------------
# == nanacl/bsearch_right from main --------------------------------------------
# frozen_string_literal: true

class Array
  def bsearch_right(&)
    index = bsearch_index_right(&)
    index && self[index]
  end

  def bsearch_index_right(&block)
    right = bsearch_index { |elem| !block.call(elem) }
    if right.nil?
      size - 1
    elsif right == 0
      nil
    else
      right - 1
    end
  end
end

class Range
  def bsearch_right(&block)
    right = bsearch { |elem| !block.call(elem) }
    if right.nil?
      last
    elsif right == first
      nil
    else
      right - 1
    end
  end
end


# ==============================================================================

main.call