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Infinitely many primes p with φ⁺(p) < φ⁺(p+1)

Ascertain whether there exist infinitely many primes p such that φ⁺(p) < φ⁺(p+1), where φ⁺(n)=∏_{q\mid n}(φ(q^{v_q(n)})+1).

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Background

Motivated by the classical open inequality for Euler’s totient function at consecutive integers, the authors prove that φ⁺(q) < φ⁺(q+1) holds for an infinite family of prime q of the form q=2p−1 (with p in OEIS A005382), and then ask whether such inequalities occur for infinitely many prime p in general.

References

Open question 6: Are there infinitely many prime $p$ such that $\varphi+(p)<\varphi+(p+1)$?

Divisibility and Sequence Properties of $σ^+$ and $\varphi^+$ (2508.11660 - Mandal, 6 Aug 2025) in Section 2, Main Results (Open question 6)