Disproofs of two conjectures concerning nondeficient numbers

Abstract

A positive integer $n$ is said to be nondeficient if $σ(n) \geq 2n$. Letting the positive divisors of a positive integer $n$ be written as $1 = d_0 < d_1 < \cdots < d_k < d_{k+1} = n$, and letting $\mathcal{S}$ denote a set of integers, if there exist values $λ_j \in \mathcal{S}$ such that $1 + \sum_{j=1}^{k} λ_j d_j = n$, then $n$ is said to be an $\mathcal{S}$-perfect number. Ross, in 2024, introduced the study of $\mathcal{S}$-perfect numbers, and concluded with two conjectures that each concern both $\{ -1, 1 \}$-perfect numbers and nondeficient numbers. We disprove both of these conjectures.