Explore the 3n + 1 sequence and observe whether it reaches 1 within the selected computation limits.
Enter positive integers for the starting value and the maximum step limit.
Steps
111
Max value
9,232
Sequence
The Collatz conjecture says that if you repeatedly apply a simple rule to any positive integer, you may eventually reach 1. It remains unproven.
If the number is even, divide by 2. If it is odd, multiply by 3 and add 1.
Invalid values are rejected instead of being parsed loosely.
Increase the limit if the sequence is long or slow to reach 1.
The result panel shows the step count, the largest value reached, and the full sequence.
Starting number: 6
6 -> 3 -> 10 -> 5 -> 16 -> 8 -> 4 -> 2 -> 1
Steps to reach 1: 8
No. It remains an open problem in mathematics.
No. The conjecture is defined here for positive integers only.
Odd values become 3n + 1, which can be much larger than the starting value.
A tiny rule creates surprisingly complicated behavior, which is why mathematicians still study it.
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