Polignac's conjecture

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Let p1<p2<p3<⋯p_1 < p_2 < p_3 < \cdots denote the increasing sequence of all prime numbers, so that pkp_k and pk+1p_{k+1} are consecutive primes for every k≥1k \ge 1. For an even positive integer nn and a real number x≥2x \ge 2, put

πn(x)=#{ k≥1  :  pk≤x,  pk+1−pk=n }.\pi_n(x) = \#\{\, k \ge 1 \;:\; p_k \le x, \; p_{k+1} - p_k = n \,\}.

For every even positive integer nn there are infinitely many indices kk with pk+1−pk=np_{k+1} - p_k = n; equivalently, πn(x)→∞\pi_n(x) \to \infty as x→∞x \to \infty for every even n≥2n \ge 2. That is, for every even n≥2n \ge 2 there are infinitely many primes pp such that p+np + n is \prime and no \prime lies strictly between pp and p+np + n.

References

Primary source

Wikipedia

Additional references

  1. Wikipedia, Polignac's conjecture, the article this problem comes from.

Progress summary

Refreshed
Claimed progress

The conjecture remains unproved, despite major progress on bounded prime gaps and unsupported claims of a complete proof.

Proposed by Alphonse de Polignac in 1849, the conjecture predicts infinitely many consecutive prime pairs at every prescribed positive even gap. No particular even gap has been proved to occur infinitely often as a consecutive-prime gap.

Known results

  • Zhang, 2013: some even gap n<70,000,000n<70{,}000{,}000 occurs infinitely often.
  • Maynard and Tao, 2013--2014: bounded-gap methods reduced the unconditional bound to 246246.
  • Chen, 1966: for every even hh, infinitely many primes pp have p+hp+h prime or semiprime.
  • Sawin and Shusterman, 2019: the analogous statement holds for prime polynomials over finite fields, not ordinary primes.

August 12 claimed proof

A post dated August 12 claimed “Proof of Polignac’s conjecture! QED.” No proof, verification, or independent confirmation is supplied in the scan. Separately, Sankei et al. published a claimed logical proof on March 16, 2024, while the article itself acknowledged that the conjecture remained unproven.

Current status (as of August 2026): Bounded gaps are known, but Polignac’s conjecture for every even nn remains open; the August 12 proof claim is unverified.

Sources

Solutions 0

No solutions have been posted yet.