# Divisibility proof

PROVE THAT 5 * 7^n + 3 * 11^n is divisible by 4 for all integers n >=0.

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PROVE THAT 5 * 7^n + 3 * 11^n is divisible by 4 for all integers n >=0

Proof. We proceed induction on n.

Base step: For n=0, since 5 * 7^0 + 3 * 11^0 =5*1+3*1=8 which is divisible by 4. So, the base step holds.

Inductive step: Assume that 5 * 7^n + 3 * ...

#### Solution Summary

The solution provides an example of a divisibility proof.

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