Seven is the sole number D for which the equation 2n − D = x2 has more than two answers for n and x normal. Specifically, the equation 2n − 7 = x2 is recognized as the Ramanujan–Nagell equation. Jahannam has seven gates that are open up always. (Qur’an – https://bathroomgrabbarsforelderl21626.bloggosite.com/45192223/top-guidelines-of-7-day-pill-organizers