2021/04/18 by Nikita Shulga, Shulga, Nikita
Mathematics · #FOS: Mathematics #Number Theory (math.NT) #math.NT
paper · pdf · doi:10.48550/arxiv.2104.08897
11 pages
arxiv created 2021/04/20 · arxiv updated 2021/04/22
For the Minkowski question mark function ?(x) we consider derivative of the function fn(x) = \underbrace?(?(...?n times(x))). Apart from obvious cases (rational numbers for example) it is non-trivial to find explicit examples of numbers x for which f'n(x)=0. In this paper we present a set of irrational numbers, such that for every element x0 of this set and for any n∈ℤ+ one has f'n(x0)=0.