Analytic number theory · primes in short intervals · sieve methods · prime gaps

Legendre Conjecture

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Is there always a prime strictly between two consecutive positive squares?

n1pP,n2<p<(n+1)2
Known results and sources
Two consecutive square milestones frame an open number-line interval containing integer points; one restrained gold point is posed as a possible prime, with no solved marker.
Legendre's conjecture asks for a prime in every open interval between consecutive positive squares.

Research problem

Exact mathematical statement

For every integer n1n\ge 1, there exists a prime pp satisfying

n2<p<(n+1)2.n^2<p<(n+1)^2.

Both inequalities are strict: in particular, the upper square is excluded. Equivalently, if π(x)\pi(x) is the prime-counting function, then π((n+1)2-1)-π(n2)>0\pi((n+1)^2-1)-\pi(n^2)>0 for every n1n\ge1. The source reports no proof; its bounded computational audit is an implementation guard, not evidence for all integers.

Problem infographic

Problem at a glance

A wide number-line explainer shows the strict interval n squared to (n+1) squared, neutral integer candidates inside, and the open universal question whether at least one prime occurs for every n at least one.
The endpoints are excluded, and the quantifier is universal: at least one prime must occur in each consecutive-square interval.

Current mathematical picture

Where work on Legendre Conjecture stands

Open conjecture

Selected route highlights from the mathematical source. This is not yet a complete mathematical inventory.

Useful failureTreating floor-free coefficient models as usable short-interval asymptotics

The source explicitly says none of its coefficient statements is a short-interval asymptotic and lists hidden prime terms, generic negative rough terms, and an all-moduli parity tail. The canonical graph, matching, triangle, and older 8/7 routes remain possible only if an exact block inventory supports a provable endpoint theorem.

Route status · Narrowed route
Main reductionCurrent reduction

The current work constructs exact pointwise prime minorants from rough factor counts and organizes their coefficients through a five-factor pair budget; positivity of the resulting interval sums would imply the target.

Evidence posture · Source-reported route statement · dependencies incomplete
Priority open bridgeDerive one common exact decomposition for the pair-budget detector family with every coefficient class and modulus range inventoried.Task status · Ready to work on
Research-record correctionResearch-record correction

We corrected the cited passages. We updated the highlighted open task or route. The mathematical claims and their status did not change.

Reader-facing record corrected; mathematics unchanged

Work mapped so far

Legendre Conjecture in numbers

2.5kretained lines of mathematical investigation2,505 in the current working snapshot
Argument development
2,233 · 89%
Explored or eliminated routes
46 · 2%
Computational analysis
38 · 2%
Open obligations
59 · 2%
Definitions and setup
129 · 5%
8selected mapped statements1routes investigated3open questions3contribution-ready tasks
How this is measured

This measures retained mathematical investigation, not proximity to a proof. Code, data, logs, repeated text, operational instructions, and generated presentation copy are excluded.

Argument map and routes

How the current approaches connect

Claims, reductions, open questions, active routes, and narrowed alternatives in one mathematical map.

Visible working map

Research route map

12 selected steps

Selected claims, active routes, useful failures, and open questions from the current research map. Arrows appear only for explicitly recorded relationships.

12 selected steps

Scroll horizontally to explore the route

Working route overview for Legendre ConjectureA selected map of recorded claims, active routes, useful failures, open questions, and their explicit relationships. Search, filter, zoom, or pan within this page.Every open interval between consecutive positive squares should contain a prime. — Depends on missing premiseEvery open interval betweenconsecutive positive squaresshould…Current reduction — Depends on missing premiseCurrent reductionBounded source-reported audit — Depends on missing premiseBounded source-reportedauditCanonical graph prime minorant — Depends on missing premiseCanonical graph primeminorantClosing target — Depends on missing premiseClosing targetFive-factor occurrence budget — Depends on missing premiseFive-factor occurrencebudgetModel coefficient is not an asymptotic — Depends on missing premiseModel coefficient is not anasymptoticStrict consecutive-square interval — Depends on missing premiseStrict consecutive-squareintervalTreating floor-free coefficient models as usable short-interval asymptotics — stoppedTreating floor-freecoefficient models as usableshort-interval…Derive one common exact decomposition for the pair-budget detector family with every coefficient class and modulus range inventoried. — OpenDerive one common exactdecomposition for thepair-budget…Prove an effective joint estimate for the prime and Buchstab coefficient classes before expansion reaches the nonoscillatory all-moduli parity tail. — OpenProve an effective jointestimate for the prime andBuchstab…Close the remaining finite range only after a valid effective large-n theorem supplies an explicit cutoff. — OpenClose the remaining finiterange only after a valideffective…
Working claimActive routeOpen, active, or blocked questionUseful failure

Working overview, not proof. The map shows selected recorded relationships; more nodes or edges do not establish correctness or completion.

Explored alternatives

Other routes

1 recorded
Narrowed routeTreating floor-free coefficient models as usable short-interval asymptotics

The source explicitly says none of its coefficient statements is a short-interval asymptotic and lists hidden prime terms, generic negative rough terms, and an all-moduli parity tail. The canonical graph, matching, triangle, and older 8/7 routes remain possible only if an exact block inventory supports a provable endpoint theorem.

Route status · Narrowed route

More ways to contribute

Open questions

Additional prepared tasks for exploring this research frontier.

3 featured tasks
01
Derive one common exact decomposition for the pair-budget detector family with every coefficient class and modulus range inventoried.Suggested move: Compare the canonical graph and hybrid detector block by block, retain floors and endpoint differences, and identify the weakest genuinely sufficient estimate.
Ready to work on
02
Prove an effective joint estimate for the prime and Buchstab coefficient classes before expansion reaches the nonoscillatory all-moduli parity tail.Suggested move: Select one sufficient completion theorem from the current work, prove it with explicit constants, and reject any route whose coefficient becomes generic before the required truncation.
Ready to work on
03
Close the remaining finite range only after a valid effective large-n theorem supplies an explicit cutoff.Suggested move: Run a deterministic segmented prime-gap verification with preserved software parameters, block hashes, primality evidence, and a reproducible transcript.
Ready to work on

Sourced mathematical context

The known mathematical landscape

Context collected Aug 14, 2026
Current statusOpen conjecture

Legendre's exact conjecture remains open. Current 2026 results prove a universal three-almost-prime analogue and conditional statements for intervals between consecutive larger powers, while the cited unconditional prime-gap theorem does not reach every interval between consecutive squares.

[2][3][1]
External progress

What the literature has established

Selected external milestones in reverse chronological order, with their evidence posture.

  1. PreprintCampbell proves that every consecutive-square interval contains an integer with at most three prime factors, an explicit almost-prime analogue that does not require the integer to be prime.[3]
  2. PreprintChamberland and Straub review the open consecutive-square problem and derive conditional results for primes between consecutive powers with exponent strictly larger than two.[2]
  3. Peer reviewedBaker, Harman, and Pintz prove a major unconditional bound on gaps between consecutive primes. The exponent remains too large to force a prime in every interval between consecutive squares.[1]
3 cited sources3 related results or reductionsReferences

Mathematical neighborhood

Related results and reusable starting points

Current focusLegendre conjecture
Weaker or relaxed formthree-almost-prime between consecutive squares

Replacing a prime by an integer with at most three prime factors yields a theorem for every interval, but permits composite witnesses.

[3]
Weaker or relaxed formprimes between consecutive larger powers

Intervals between consecutive powers with exponent larger than two are wider than consecutive-square intervals; the reviewed all-x results also assume the Riemann hypothesis.

[2]
Dependency or reductionuniform maximal prime-gap bounds

A sufficiently strong uniform bound on maximal prime gaps near x would imply the conjecture, but the cited unconditional exponent does not reach square-root-length intervals.

[1]

Formal and computational footholds

Existing statements, libraries, computations, and datasets that can shorten the next serious attempt.

  • computation · not independently reproducedFinite verification used in the three-almost-prime theorem

    The preprint reports finite verification through a large explicit range as one component of its almost-prime theorem; this staging lane did not run or audit that computation.

    [3]

Formalization opportunities

Lean work can make these reusable foundations precise without being presented as a proof of the core problem.

  • Formalization targetA problem-level statement requires exact open endpoints and primality, not an almost-prime predicate.
  • Formalization targetA universal proof needs both an effective large-n theorem at consecutive-square scale and reproducible closure of the remaining finite range.

Research-record corrections

What changed in the research record

These notes describe corrections to cited passages, highlighted tasks, or connections between claims. The mathematical claims and their status did not change.

Research-record correctionWe corrected the cited passages. We updated the highlighted open task or route. The mathematical claims and their status did not change.

Corrected the research recordCorrection note

Correction details
Research-record correctionWe corrected the cited passages. We removed a duplicate or outdated task or route step. We updated the highlighted open task or route. The mathematical claims and their status did not change.

Corrected the research recordCorrection note

Correction details

The initial argument structure appears separately. Uploads, model runs, and presentation changes do not count as mathematical updates.

Detailed research inventory

Claims, milestones, and routes in the current map

This view highlights the mathematical statements most useful for following the current route.

6 standing statements2 proposed statements3 open questions1 narrowed routes
Statements by mathematical role8 selected mapped statements
  • theorem candidate1 of 81
  • reduction1 of 81
  • lemma4 of 84
  • negative result1 of 81
  • computational claim1 of 81
Selected mathematical clusters1 mathematical clusters
Current research mapThe conjecture, retained reductions, explored limitations, and open questions represented in this overview.22 displayed rows · 1 route included
  • retained route statementEvery open interval between consecutive positive squares should contain a prime.
  • retained route statementCurrent reductionintermediate
  • retained route statementClosing targetintermediate
  • retained route statementStrict consecutive-square intervalintermediate
  • retained route statementFive-factor occurrence budgetintermediate
  • retained route statementCanonical graph prime minorantintermediate
  • retained route statementModel coefficient is not an asymptoticintermediate
  • retained route statementBounded source-reported auditintermediate
  • Recorded relationshipThe source reports this as a route toward the conjecture; missing or unaudited premises remain and the reduction does not itself prove the target.supports · reported by source
  • Recorded relationshipThis source-reported claim supports the retained route only within its stated, unaudited scope.supports · reported by source
  • Recorded relationshipThis source-reported claim supports the retained route only within its stated, unaudited scope.supports · reported by source
  • Recorded relationshipThis source-reported claim supports the retained route only within its stated, unaudited scope.supports · reported by source
  • Recorded relationshipThis source-reported claim supports the retained route only within its stated, unaudited scope.supports · reported by source
  • Recorded relationshipThis source-reported claim supports the retained route only within its stated, unaudited scope.supports · reported by source
  • DerivationThe source reports that completing the closing target would advance the reduction to the main conjecture; this remains an informal route, not a verified derivation.proposed
  • Useful failureTreating floor-free coefficient models as usable short-interval asymptoticsreported failure
  • Research targetDerive one common exact decomposition for the pair-budget detector family with every coefficient class and modulus range inventoried.open
  • Research targetProve an effective joint estimate for the prime and Buchstab coefficient classes before expansion reaches the nonoscillatory all-moduli parity tail.open
  • Research targetClose the remaining finite range only after a valid effective large-n theorem supplies an explicit cutoff.open
  • Research targetJoint coefficient-class estimatesuperseded
  • ComputationThe source says a sieve script checked the stated identities for every 2≤n≤2000; this staging lane did not execute it.Source-reported only: 4,001,998 interval integers were examined; the current work explicitly says the counts are a guard against mistakes, not a proof. · reported unreproduced
  • Narrowed routeTreating floor-free coefficient models as usable short-interval asymptoticsThe source explicitly says none of its coefficient statements is a short-interval asymptotic and lists hidden prime terms, generic negative rough terms, and an all-moduli parity tail. The canonical graph, matching, triangle, and older 8/7 routes remain possible only if an exact block inventory supports a provable endpoint theorem.
How to interpret these counts

A statement may be a lemma, conditional reduction, special case, documented limitation, or open target. These counts describe the work's structure; they do not estimate distance to a proof.

Research outlook

Conditions that would advance the current route

Priority open bridgeDerive one common exact decomposition for the pair-budget detector family with every coefficient class and modulus range inventoried.

1 approach has already been tested and narrowed. The task above is the current priority within the larger open route.

Evidence needed nextConcrete conditions for progress

A result can change the outlook by closing the bridge, narrowing its scope, or showing that the route cannot work.

  • Supply a complete argument with every imported premise identified.
  • Survive an independent attempt to falsify the proposed step.

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Prepared starting pointDerive one common exact decomposition for the pair-budget detector family with every coefficient class and modulus range inventoried.

Legendre Conjecture · ready to start

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Research contextPrepared context for any AI agent

Is there always a prime strictly between two consecutive positive squares?

  • Exact question and boundaries
  • Current routes and known obstacles
  • What a useful result should report
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Sources and references3 cited works · next context review by Nov 14, 2026

The mathematical context was checked on Aug 14, 2026. Status can be refreshed sooner after a material result or claim.

  1. 1
    On the difference between consecutive primes, IIpeer reviewed result · Roger C. Baker, Glyn Harman, János Pintz · Proceedings of the London Mathematical Society · 2001 · DOI 10.1112/plms/83.3.532 · accessed Aug 14, 2026
  2. 2
    Weakening the Legendre Conjecturepreprint · Marc Chamberland, Armin Straub · arXiv · 2026-02-26 · ARXIV 2602.22502 · accessed Aug 14, 2026
  3. 3
    On the Existence of Integers with at Most 3 Prime Factors Between Every Pair of Consecutive Squarespreprint · Peter Campbell · arXiv · 2026-03-11 · ARXIV 2603.10356 · accessed Aug 14, 2026

Important qualifications

  • The exact target requires a prime strictly between every pair of consecutive positive squares; almost-primes, conditional results, and intervals between larger powers are weaker statements.
  • The current almost-prime preprint and its cited computation were not independently reproduced in this lane.
  • No packet computation or submitted URL was used as external status authority.
  • The source list is representative rather than an exhaustive history of prime-gap results.

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