The expressions φ(n) + σ (n) − 3n and φ(n) + σ (n) − 4n are unusual among linear combinations of arithmetic functions in that they each vanish on a nonempty set of composite numbers. In 1966, Nicol proved that the set A := {n | (φ(n) + σ (n))/n ∈ N 3 } contains 2 a · 3 · (2 a−2 · 7 − 1) if and only if 2 a−2 · 7 − 1 is prime and conjectured that A contains no odd integers. A 2008 paper by Luca and Sandor completely classifies the elements of A that have three distinct prime factors and observes that Nicol's conjecture holds for numbers with fewer than six distinct prime factors. In this paper we let A K denote the set of n ∈ A with exactly K distinct prime factors and present a computer-implementable algorithm that decides whether Nicol's conjecture holds for a given A K . Using this algorithm, we verify Nicol's conjecture for A 6 and completely classify the elements of A 4 . We prove that all but finitely many n ∈ A 4 have the form 2 a · 3 · p 3 · p 4 , and that all but finitely many n ∈ A 5 are divisible by 6 and not 9. In addition, we prove that every A K is contained in a finite union of sequences that each have the form {pp 1 , . . . , p k are distinct primes, and each a ji as well as the least prime factor of w i go to infinity as i does.