forms of this conjecture and a slight generalization of a former result from [1]. Then, we
present the notion of “chain subtrees” in Collatz's tree followed by a characterization
theorem and some subclass of numbers which are labels for some chain subtrees. Next, we
define the notion of “fixed points” and using this, we give another conjecture similar to
Collatz's conjecture. Some new infinite sets of numbers for which the Collatz's conjecture …