Rule: if n even: n→n/2
if n odd: n→3n+1
Conjecture (Collatz, 1937):
Every n eventually → 1.
Verified for n < 2⁶⁸ (~2×10²⁰)
Erdős: "Math is not yet ready
for such problems."
n=27 takes 111 steps, reaches
maximum of 9232 — extraordinary
for such a small start.
Steps: —
Max value: —