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Handelman's Conjecture on integrability of h from integrability of h(x)/h(2x) under ratio-limit condition

Establish that if h:(0,∞)→(0,∞) is log convex, satisfies lim_{n→∞} h(n+1)/h(n) = 1, and h(x)/h(2x) is integrable on (0,∞), then h is integrable on (0,∞).

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Background

Following the discussion after Theorem 9 in Handelman (1996), the paper states a conjecture linking the integrability of the ratio h(x)/h(2x) to the integrability of h itself, under a discrete ratio-limit condition on h at integers.

This conjecture is recorded in the introduction as Conjecture 1, and later shown to be true in Theorem 2.

References

Conjecture 1. Suppose h : (0,∞) → (0,∞) is a log convex function that satisfies

h(n) (1) n→∞m h(n + 1) = and h (x)/h(2x) is integrable on (0,∞). Then h is also integrable on (0,∞).

On Some Convexity Questions of Handelman (2402.10970 - Simanek, 14 Feb 2024) in Section 1 (Introduction), Conjecture 1