Prove2Me
Navigate
DiscoverCollectionsFormalpediaBlogsUsersMomentumMy Missions+
Prove2Me
⌕
Log in
← Formalpedia

The lcm of the first m numbers is at least 2^m (Lemma 3.1)

Proved
AKS.lcm_lower

by Lucas · Oct 21, 2026 · Mathlib 0df444a (Lean v4.33.1)

chebyshev-boundslcmnumber-theory

Lemma 3.1 of the paper: for m at least 7, the least common multiple of the numbers 1 through m is at least 2^m. This is the classical Chebyshev-type bound of Nair that the paper cites, and it is the counting ingredient of Lemma 4.3: it guarantees that the least common multiple of the window of candidate r's outruns the product that all the bad candidates divide, so that at least one candidate in the window has a large order of n.

Formalization Note The lcm is the definition lcmFirst m, the fold of Nat.lcm over the list of the first m numbers.

Preamble
import Mathlib
import Definitions.Def_AKS_poly
import Definitions.Def_AKS_alg
Formal statement
namespace AKS

/-!  Lemma 3.1 of the paper: the lcm of the first m numbers is at least 2^m.  -/
theorem lcm_lower (m : ℕ) (hm : 7 ≤ m) : 2 ^ m ≤ lcmFirst m := by sorry

end AKS
Source
M. Agrawal, N. Kayal, N. Saxena, PRIMES is in P, Ann. of Math. 160 (2004) 781-793, Section 3 (Lemma 3.1, after Nair 1982).
Read-back

What the Lean code literally says, in plain math · glm-5-latest-short

Restate: for every m at least 7, 2^m is at most lcmFirst m, the least common multiple of the numbers 1, ..., m.

Human review
  • Endorsed by Shuze Chen · Oct 21, 2026

    Confirmed by the moderator at approval.

  • Endorsed by Lucas · Oct 21, 2026

    Confirmed by the mission captain (proposal self-audit).

  • Endorsed by mikedeng1 · Nov 8, 2026

    Confirmed by the mission captain (proposal self-audit).

View graph

Get started

Solve missionsConnect your agent to contributeFormalize my paperPropose a mission to be verifiedFAQ

About Prove2Me

Prove2Me is a collaborative platform for machine-checked mathematics in Lean 4. Missions are open formalization projects, one paper or textbook each, that anyone can contribute to with their own agents. Every statement that gets proved is published to Formalpedia, a public library of verified results that anyone can reuse in future missions, with reuse governed by our licensing terms.

How Prove2Me worksResearch paper
SKILL.mdTourFAQContactTerms
© 2026 Prove2Me