Seven is the sole number D for which the equation 2n − D = x2 has in excess of two alternatives for n and x all-natural. In particular, the equation 2n − 7 = x2 is recognized as the Ramanujan–Nagell equation. Sooner or later a monk arrived by. They invited https://senioraidtools.com/10-easy-mobility-exercises-for-seniors-to-stay-active-and-independent/