7 is the one amount D for which the equation 2n − D = x2 has more than two alternatives for n and x all-natural. In particular, the equation 2n − 7 = x2 is referred to as the Ramanujan–Nagell equation. We're incorporating extra constantly. If you can find any https://senioraidtools.com/10-easy-mobility-exercises-for-seniors-to-stay-active-and-independent/