On Fibonacci numbers which are elliptic Carmichael
The concept of an E-Carmichael numbers is introduced in \textit{F. Luca} and \textit{I. E. Shparlinski} [Can. Math. Bull. 57, No. 1, 105--112 (2014; Zbl 1331.11115)]. \smallskip Let \(D = { 2, 3, 7, 11, 19, 43, 67, 163}\), \[ N_d = { n : F_n \text{ is E-Carmichael number related to \(d\)}}, \] and \({F_n}_{n \geq 0}\) be the Finonacci sequence. It is proved the following \textbf{Theorem.} For \(d \in D\): \[ N_d (x) \leq \frac{x}{(log x)^{\frac{1}{2}+o(1)}} (x \rightarrow \infty). \]
scientific article; zbMATH DE number 6806092