Let A be a set of positive integers. We define a positive integer n as an A-practical number if every positive integer from the set \1,… ,∑d∈ A, d nd\ can be written as a sum of distinct divisors of n that belong to A. Denote the set of A-practical numbers as Pr(A). The aim of the paper is to explore the properties of the sets Pr(A) (the form of the elements, cardinality) as A varies over the power set of N. We are also interested in the set-theoretic and dynamic properties of the mapping PR:P(N) A(A)(N).
No takes yet. Share an insight, caveat, or question.
Kukla et al. (2024) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: