prime_unixtime.rb

def is_prime?(number)
  return false if number == 2
  return false if (number % 2).zero?
  i = 3
  while i * i < number
    return false if (number % i).zero?
    i += 2
  end
  true
end

time = Time.now.to_i

time += 1 if (time % 2).zero?

while true
  if is_prime?(time)
    puts "#{time} #{Time.at(time)} is a prime unixtime"
  end
  time += 2
end