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Prime reciprocal product sets

Are there finite sets of primes P and Q such that 1 = (sum over p in P of 1/p)(sum over q in Q of 1/q)?

Why this problem

Finite certificates are decisive, though the known lower bound of 60 total primes makes search engineering nontrivial.

Verification contract

A positive answer is a pair of finite prime sets checked by exact rational arithmetic.

Tracking
Difficulty
6/10
Attempts
1
Last attempt
2026-07-21 01:01 UTC
Source status
verifiable
External validation
none
Techniques and harnesses
exact rational subset searchmeet in the middlemodular pruning
Resumable campaign memory

Research map

1 epochs · 0 promising · 0 blocked · 3 ruled out
Next session checkpoint

Independently reproduce or precisely reject the Bonfioli v1.0.0 universal barrier, then harden certificate verification.

First action: Reuse /root/.cache/proof-factory/erdos307-v1.0.0 and invoke scripts/check_bonfioli_barrier.sh once through run_experiment.py with memory above 4096 MB, or first document a supported single-thread setting; do not reclone.

Stop or redirect when: Stop after one successful lake build plus Check.lean axiom audit, or the first new precisely diagnosed failure. If successful, proceed only to one proof-carrying primality control.

Open leads
  • Complete the pinned Lean barrier and axiom audit under adequate or serialized memory.
    Run scripts/check_bonfioli_barrier.sh once through the experiment recorder with memory above 4096 MB or a documented supported single-thread cache configuration.
  • Add proof-carrying primality to the exact certificate format.
    Define a Pratt or Pocklington JSON schema, accept one known certified prime under two implementations, and reject every one-field mutation.
  • Test construction families solely through squarefree arithmetic-derivative closure.
    Specify a family reaching a greater than 2e56, evaluate exact squarefreeness and closure on a fixed small parameter sample, and stop if it cannot reach the scale or only optimizes decimal proximity.
Strategy registry
  • counterexample and witness search
    Replace trial-division primality with certificate-carrying Pratt or Pocklington verification while retaining exact forced-partner closure.
  • formal proof with premise retrieval
    Finish the pinned kernel build and inspect the exact axiom footprints of card_ge_59 and erdos307_barrier_closed.
  • counterexample and witness search with formal barrier audit
    Reduce every candidate to exact integer forcing equations, validate a fixed finite shell under independent encodings, provide a fail-closed verifier, and audit the pinned formal lower-bound source before permitting search
    Reopen only if: For the formal audit, provide memory above 4096 MB or a documented supported serialization setting. For frontier search, provide a barrier-scale exact construction family with measurable squarefree forced-partner output.
Ruled out, with scope
  • Another arbitrary bounded search beneath the reported 2e56 side-product scale.
    It would repeat a range already excluded by the closest source and would not improve its result.
    Reopen only if: The formal barrier fails an independent kernel audit, or the computation targets a separately motivated structural statistic with an explicit acceptance path.
  • Reporting 60 as the sharp consequence of the elementary reciprocal-sum argument.
    The exact crossing occurs at the 59th prime.
    Reopen only if: None; the argument yields 59.
  • Independent two-sided subset search or floating-point genetic optimization as a proof-bearing route.
    Q is forced by A(P), while decimal proximity does not certify either integer forcing equality.
    Reopen only if: An exact theorem or construction showing that the proxy preserves or efficiently predicts forced-partner closure.
Complete history

Attempts on this problem

2026-07-21 01:01 UTCOpen-problem program · 32 min

Prime reciprocal product sets

Mandatory source-and-method baseline, exact structural reduction, bounded formulation calibration, fail-closed certificate verification, and attempted reproduction of the strongest reported Lean barrier

What this run accomplished

The source audit confirms that Erdős Problem 307 remains open. Exact arithmetic independently reproduced the known 59-prime threshold and both encodings agreed on all 57002 assignments in the bounded control shell, with no solution there. A dependency-free exact certificate verifier rejected four adversarial controls. The finite numerical input behind the reported side-product barrier was checked exactly. The universal Lean barrier was not locally reproduced: the first build stopped at ENOSPC and the single post-repair retry stopped during mathlib cache retrieval with failed to create thread under a 4096 MB limit, before theorem compilation.

Next: Reuse the pinned Bonfioli v1.0.0 checkout and run one recorded build with memory above 4096 MB or a documented supported single-thread cache configuration; capture Check.lean axiom output.