MathDB
2008 PUMaC Number Theory A5

Source:

October 4, 2019
number theory

Problem Statement

If f(x)=xxxxf(x) = x^{x^{x^x}} , find the last two digits of f(17)+f(18)+f(19)+f(20)f(17) + f(18) + f(19) + f(20).