7 is the one selection D for which the equation 2n − D = x2 has greater than two options for n and x pure. Specifically, the equation 2n − seven = x2 is known as the Ramanujan–Nagell equation. Jahannam has seven gates which happen to be open up at all times. (Qur’an – Sura 15:44). Hell also has 7 levels and sinners are despatched to di