Seven is the only quantity D for which the equation 2n − D = x2 has much more than two options for n and x purely natural. Particularly, the equation 2n − 7 = x2 is referred to as the Ramanujan–Nagell equation. One day a monk arrived by. They invited https://mobility-exercises-for-se42962.life-wiki.com/1842927/not_known_facts_about_7_day_pill_organizers