How to prove that $2^{2n + 1} - 9n^2 + 3n - 2$ is divisible by $54$ for $n \in \mathbb{N} \cup \{0\}$?
Prove by induction that for every $n \ge 0$ the term $2^{2n+1} - 9n^2 + 3n -2$ is divisible by $54$
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