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Composite values of F(2^n)+h for the Fibonacci sequence

Prove or disprove that for any integer h, the numbers F(2^n)+h are composite for infinitely many integers n, where F(n) denotes the Fibonacci sequence.

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Background

To relax the strong reversibility assumption in their main theorems, the authors propose studying sequences that combine non-reversible exponential growth (2n) with a classical linear recurrence (Fibonacci). Establishing compositeness of F(2n)+h infinitely often would be a step toward removing the reversibility condition and could shed light on related divisibility phenomena.

References

Let (F(n))_{n\ge 1} be the Fibonacci sequence. Let h be an arbitrary integer. Prove or disprove that the numbers F(2n)+h are composite for infinitely many n.

Intervals without primes near an iterated linear recurrence sequence (2504.14968 - Saito, 21 Apr 2025) in Problem (following the discussion on reversibility), Introduction