= Satisfying-assignment count for nested implications
{title2=$\#\{v:v\models A_n\to(\cdots\to(A_2\to A_1))\}=2^n-1$}
For distinct propositional variables, eliminate each right-associated <logical implication> to obtain $\neg A_n\lor\cdots\lor\neg A_2\lor A_1$. Exactly one <Boolean valuation> falsifies all these disjuncts: $A_1=0$ and $A_2=\cdots=A_n=1$. Of the $2^n$ assignments, the other $2^n-1$ are <satisfying assignments>. Left-associated implication chains have a different meaning and need not have the same count.
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