def definition def or abbrev

`phi`

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

formal statement (Lean)

  54noncomputable def phi : ℝ := (1 + Real.sqrt 5) / 2

Definition body.

  55
  56/-- φ satisfies the fixed-point equation φ² = φ + 1. -/

Lean names referenced from this declaration's body.