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Source labels openChecked July 26, 2026

WikipediaNumber theory

First Hardy–Littlewood conjecture

For integers x,y2x, y \geq 2, π(x+y)π(x)+π(y),\pi(x + y) \leq \pi(x) + \pi(y), where π(z)\pi(z) denotes the prime-counting function, giving the number of primes up to and including zz.

Mathematical statement

For integers x,y2x, y \geq 2,

π(x+y)π(x)+π(y), \pi(x + y) \leq \pi(x) + \pi(y),

where π(z)\pi(z) denotes the prime-counting function, giving the number of primes up to and including zz.

Statement source: Wikipedia statement material

Statement terms: CC-BY-SA-4.0

Attributed source material. Reuse must follow the linked attribution and share-alike terms.

Statement artifacts, not proofs

These records expose exact Lean propositions and statement-only wrappers. Defining a proposition does not supply a proof of it. A placeholder-bearing target also contains no proof. Elaboration checks syntax and types; it does not certify that a formalization perfectly captures every nuance of the informal problem.

Pinned Lean formulation 1

second_hardy_littlewood_conjecture

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem second_hardy_littlewood_conjecture {x y : } (hx : 2  x) (hy : 2  y) :    SecondHardyLittlewoodConjectureFor x y := by  sorry
Statement source
Formal Conjectures
Lean version
v4.27.0
Placeholder
Present; no proof artifact
Source evidence
Pinned source index
Fidelity review
Community formulation

References