Revisited carmichael's reduced totient function

Abstract

The modified Totient function of Carmichael ?(.) is revisited, where important properties have been highlighted. Particularly, an iterative scheme is given for calculating the ?(.) function. A comparison between the Euler ? and the reduced totient ?(.) functions aiming to quantify the reduction between is given. 2021 by the authors. Licensee MDPI, Basel, Switzerland.