7 is the only real variety D for which the equation 2n − D = x2 has over two answers for n and x organic. In particular, the equation 2n − 7 = x2 is called the Ramanujan–Nagell equation. Jahannam has 7 gates which might be open up at all times. (Qur’an – Sura 15:forty four). Hell also has 7 levels and sinners are sent to distinctive le