Seven is the only variety D for which the equation 2n − D = x2 has in excess of two solutions for n and x normal. In particular, the equation 2n − seven = x2 is referred to as the Ramanujan–Nagell equation. 2 hours in the past By Mashable Workforce https://augustrrmhz.win-blog.com/18746046/top-guidelines-of-7-day-pill-organizers