Article ID Journal Published Year Pages File Type
4594290 Journal of Number Theory 2012 21 Pages PDF
Abstract

We study the solutions of the equation ϕ(Cm)/ϕ(Cn)=r, where r is a fixed rational number, Ck is the kth Catalan number and ϕ is the Euler function. We note that the number r=4 is special for this problem and for it we construct solutions (m,n) to the above equation which are related to primes p such that 2p−1 or 4p−3 is also prime.

Related Topics
Physical Sciences and Engineering Mathematics Algebra and Number Theory