Collatz Conjecture

If n is even → n/2; if odd → 3n+1. Does it always reach 1?

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peak value
Collatz conjecture (1937): For any positive integer n, the sequence:
• n even → n/2
• n odd → 3n+1
eventually reaches 1.

Still unproven. Erdős: "Mathematics is not yet ready for such problems."

Verified up to 2⁶⁸ ≈ 2.95×10²⁰.

Stopping time: steps to reach a number smaller than n.
n=27 has 111 steps and peaks at 9232.