Seven is the only real number D for which the equation 2n − D = x2 has a lot more than two methods for n and x all-natural. Particularly, the equation 2n − 7 = x2 is recognized as the Ramanujan–Nagell equation. Polynices was among the list of 7 commanders. https://bathroom-grab-bars-for-el24292.thechapblog.com/36820338/not-known-details-about-7-day-pill-organizers