Assumption: Shifty coin only switches if weighed. I believe this is optimal solution; if (case 1) otherwise (case 2) If it is Case 1; if (Case 1.1 - They are equal) if (Case 1.2 - They are not equal) then if Case 2 happens (no balance at first weighing); if there is balance (Case 2.1), (also meaning it was heavier at first) if no balance again as ...


With the conditions stated in the problem, you cannot possibly find the shifty coin in less than This is because This means that Since you can't do better than what I've stated, it's easy to find a solution, there are many permutations, here's an example:

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