Research project

Robin Extrema and Counterexample Support Bounds

Extremal values of Grönwall’s ratio for with a fixed number of distinct prime factors, the gap between integer and real-exponent optima, and bounds for counterexamples to Robin’s inequality.

Current state

The main manuscript characterizes the integer and real-exponent optimizers when the number of distinct prime factors is fixed and at least six. It evaluates the gap between their logarithmic objective values asymptotically and gives a finite search for the integer maximum, assuming exact comparisons. The search uses the classical exponent ordering for colossally abundant numbers. Finite computations settle the small-support cases and the transition at in the problem . The interval implementation certifies the reported cases and stops if it cannot resolve a comparison.

A separate manuscript proves unconditionally that any counterexample to Robin’s inequality has more than distinct prime factors. The proof uses elementary size bounds, Polak’s primewise decomposition, and explicit estimates for primes and zeros of the zeta function. A certificate computed with interval arithmetic verifies the numerical inequalities.

Future plans

I want to turn the finite characterization into a general numerical solver with proved comparison and termination guarantees, make the rounding estimates effective, and complete the comparison with earlier work on superabundant and colossally abundant numbers. I am also interested in the corresponding extremal problems for other multiplicative functions and for Beurling prime systems.

Details

Phase
Two public manuscripts
Domain
Analytic number theory · discrete optimization · computational verification
My role
Author