palindrome.lua

function is_palindrome(n)
  str = tostring(n)
  return str == string.reverse(str)
end

for p = 1, 9 do
  n = 9 * p + 1
  for j = 1, n do
    if n % j == 0 then
      a = 1001 - n // j
      b = 1001 - 11 * j
      test = a * b
      if is_palindrome(test) then
        print(tostring(test))
      end
    end
  end
end

palindrome.rb

def palindrome? n
  n.to_s == n.to_s.reverse
end

for p in 1...9
  n = 9 * p + 1
  for j in 1...n
    if n % j == 0
      a = 1001 - n / j
      b = 1001 - 11 * j
      test = a * b
      if palindrome?(test)
        puts "#{test}\n"
      end
    end
  end
end