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declared disproved (Lean) · formalized · $25erdos:426
False ↔ ∃ c, 0 < c ∧ ∃ᶠ (n : ℕ) in Filter.atTop, ∃ H, c * (2 ^ n.choose 2 / ↑n.factorial) ≤ ↑H.uniqueSubgraphCount
graph theorypossible5 sources
declared disproved (Lean)erdos:608
Erdős problem 608
graph theoryN/A2 sources
declared disproved (Lean) · formalizederdos:613
False ↔ ∀ n ≥ 3, ∀ (V : Type u_1) [inst : Fintype V] (G : SimpleGraph V) [inst_1 : DecidableRel G.Adj], G.edgeFinset.card = (2 * n + 1).choose 2 - n.choose 2 - 1 → ∃ B D, ∀ [DecidableRel B.Adj] [inst_3 : DecidableRel D.Adj], G = B ⊔ D ∧ B.IsBipartite ∧ ∀ (v : V), D.degree v < n
graph theoryN/A5 sources
declared disproved (Lean) · formalizederdos:666
False ↔ ∀ (ε : ℝ), 0 < ε → ∀ᶠ (n : ℕ) in Filter.atTop, ∀ H ≤ SimpleGraph.hypercube n, ε * ↑n * 2 ^ (n - 1) ≤ ↑H.edgeSet.ncard → (SimpleGraph.cycleGraph 6).IsContained H
graph theorypossible5 sources
declared disproved (Lean) · formalizederdos:751
False ↔ ∀ (k : ℕ), ∃ V G, G.chromaticNumber = 4 ∧ ∀ m ∈ G.cycleLengths, ∀ m' ∈ G.cycleLengths, m < m' → m + k ≤ m'
graph theorychromatic numberN/A5 sources
declared disproved (Lean) · formalizederdos:753
False ↔ ∃ c, 0 < c ∧ ∀ (n : ℕ), 0 < n → ∀ (G : SimpleGraph (Fin n)), ↑n ^ (1 / 2 + c) < ↑(Erdos753.listChromaticNumber G) + ↑(Erdos753.listChromaticNumber Gᶜ)
graph theorychromatic numberN/A5 sources
declared disproved (Lean) · formalizederdos:762
False ↔ ∀ (V : Type u_1) [Fintype V] (G : SimpleGraph V), G.CliqueFree 5 → 4 ≤ G.cochromaticNumber → G.chromaticNumber ≤ G.cochromaticNumber + 2
graph theorychromatic numberN/A5 sources
declared disproved (Lean) · formalizederdos:775
False ↔ ∃ C, ∃ᶠ (n : ℕ) in Filter.atTop, ∃ H, n - C ≤ H.cliqueSizes.ncard
graph theoryhypergraphspossible5 sources
declared disproved (Lean) · formalizederdos:794
False ↔ ∀ (n : ℕ) (H : Finset (Finset (Fin (3 * n)))), H.IsThreeUniform → n ^ 3 + 1 ≤ H.card → H.ContainsSubgraph 4 3 ∨ H.ContainsSubgraph 5 7
graph theoryhypergraphsturan numberN/A5 sources
declared disproved (Lean)erdos:927
Erdős problem 927
graph theorypossible3 sources
declared disproved (Lean) · formalizederdos:1034
False ↔ ∀ (ε : ℝ), 0 < ε → ∀ᶠ (n : ℕ) in Filter.atTop, ∀ (G : SimpleGraph (Fin n)), ↑n ^ 2 / 4 < ↑G.edgeSet.ncard → ∃ T, G.IsNClique 3 T ∧ ∃ Y, Erdos1034.JoinedToTwo G T Y ∧ (1 / 2 - ε) * ↑n < ↑Y.card
graph theorypossible5 sources
declared disproved (Lean) · formalizederdos:1037
False ↔ ∀ (ε : ℝ), 0 < ε → ∀ (C : ℝ), ∀ᶠ (n : ℕ) in Filter.atTop, ∀ (G : SimpleGraph (Fin n)), (∀ (d : ℕ), {v | (G.neighborSet v).ncard = d}.ncard ≤ 2) → (1 / 2 + ε) * ↑n < ↑(Set.range fun v => (G.neighborSet v).ncard).ncard → ∃ s, Erdos1037.IsTrivialSet G s ∧ C * Real.log ↑n < ↑s.ncard
graph theoryN/A5 sources
declared disproved (Lean) · formalizederdos:1067
False ↔ ∀ (V : Type) (G : SimpleGraph V), G.chromaticCardinal = Cardinal.aleph 1 → ∃ H, H.coe.chromaticCardinal = Cardinal.aleph 1 ∧ H.coe.InfinitelyConnected
graph theoryset theoryN/A5 sources
declared disproved (Lean) · formalizederdos:1080
False ↔ ∃ c > 0, ∀ (V : Type) [inst : Fintype V] [Nonempty V] (G : SimpleGraph V) (X Y : Set V), Erdos1080.IsBipartition G X Y → X.ncard = ⌊↑(Fintype.card V) ^ (2 / 3)⌋₊ → ↑G.edgeSet.ncard ≥ c * ↑(Fintype.card V) → ∃ v walk, walk.IsCycle ∧ walk.length = 6
graph theorypossible5 sources