7 is the only number D for which the equation 2n − D = x2 has over two answers for n and x natural. Particularly, the equation 2n − seven = x2 is recognized as the Ramanujan–Nagell equation. Sooner or later a monk arrived by. They invited him to stay https://andresgicul.blogitright.com/38023945/details-fiction-and-7-day-pill-organizers