*3x+1*problem. Many others have not, I'm sure.

Here it is, in my words:

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Take any integer greater than zero. Call this number x.

If it is even, halve it. In other words, x becomes x/2

If it is odd, x becomes 3x+1

The sequence, for all numbers tested so far, ends up in the endlessly repeating loop of 4,2,1,4,2,1,4,2,1...

While many numbers have been tested by computers, this doesn't prove or disprove the conjecture that the sequence will fall into this loop. Can you provide a counterexample (it would have to be BIG), or give a proof as to why it always iterates to 1, or a proof why it sometimes doesn't? Will you be the first?

Just curious to see what you guys find.