pith. machine review for the scientific record. sign in
lemma proved term proof

phi_bound_lower

show as:
view Lean formalization →

No prose has been written for this declaration yet. The Lean source and graph data below render without it.

generate prose now

formal statement (Lean)

  56lemma phi_bound_lower : (1.618033988 : ℝ) ≤ Real.goldenRatio := by

proof body

Term-mode proof.

  57  -- golden ratio > 1, and 1.618... is a safe lower bound
  58  have h := Real.goldenRatio_gt_one
  59  linarith
  60

depends on (5)

Lean names referenced from this declaration's body.