Exercise
9
[1X7]Prerequisites:[08Z].Adapt the exercise [08Z] to define the Fibonacci sequence, which satisfies the rule
\[ a_ 0=1\quad ,\quad a_ 1=1\quad ,\quad a_ n=a_{n-1}+a_{n-2} \]
for \(n≥ 2\).
Hint. You don’t have to rewrite the whole proof of [08Z], rather choose \(A=ℕ^ 2\) and choose \(g\) with cunning.
Solution
1