7 is the only amount D for which the equation 2n − D = x2 has a lot more than two remedies for n and x natural. Especially, the equation 2n − seven = x2 is recognized as the Ramanujan–Nagell equation. Numerous Jews could have on a torn, black ribbon https://marcowxvth.blogadvize.com/45801072/about-7-day-pill-organizers