# 13 coins of which 2 may be counterfeit?

You are presented with a set of 13 suspect coins. Of these, it is
known that the number of counterfeit coins is 0 - 2. All of
the counterfeit coins, if any, are lighter OR heavier than the norm.. You must identify the counterfeit coins, if
any, after 4 weightings or fewer.

Work the Problem into a guess pattern that can be applied to any of the three possible results of a two-pan balance scale.

To recap:
N(coins) = 13
The number of weighs is 4
There can be up to two counterfeit coins.
You’re right the 81 points would bring it over the required for 4 or less weighs.

Lets assume their heavy and the first weigh is ALWAYS balanced.

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