MathDB
A Giant Expansion

Source:

November 13, 2005
AMCAIME

Problem Statement

Let x=4(5+1)(54+1)(58+1)(516+1).x=\frac{4}{(\sqrt{5}+1)(\sqrt[4]{5}+1)(\sqrt[8]{5}+1)(\sqrt[16]{5}+1)}. Find (x+1)48(x+1)^{48}.