To prove by mathematical induction: first prove for n = 1 ie. substitute n=1 and show that the formula holds for this value.
Then assume true for n = b: so in this case assume
Then, using the assumption, prove that the formula holds for n=b+1.
I'm tipping that the Godfather's problem was the third step of the inductive proof. So here's my help to prevent the mathematics getting murdered:
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