Phyllotaxis — Golden Angle & Fibonacci

Parameters

Mathematics

θ_golden = 2π/φ² ≈ 137.508°
φ = (1+√5)/2 ≈ 1.618... (golden ratio)

r_n = c√n, angle_n = n · θ

Why golden angle?
Any rational fraction p/q creates q radial arms. Only irrational angles fill space without arms. The golden ratio is the "most irrational" number — worst approximated by rationals — giving the most uniform packing.

Fibonacci spirals: Seed #n is visible in Fibonacci-numbered clockwise and counter-clockwise spiral families. In sunflowers: 34 and 55, or 55 and 89.