User:Prime.mover/Proof Structures/Proof by Complete Induction

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Proof by Complete Induction

The proof proceeds by strong induction.

For all $n \in \Z_{\ge 0}$, let $\map P n$ be the proposition:

$proposition_n$


$\map P 0$ is the case:

$proposition_0$

Thus $\map P 0$ is seen to hold.


Basis for the Induction

$\map P 1$ is the case:

$proposition_1$


Thus $\map P 1$ is seen to hold.


This is the basis for the induction.


Induction Hypothesis

Now it needs to be shown that if $\map P j$ is true, for all $j$ such that $0 \le j \le k$, then it logically follows that $\map P {k + 1}$ is true.


This is the induction hypothesis:

$proposition_k$


from which it is to be shown that:

$proposition_{k + 1}$


Induction Step

This is the induction step:

\(\ds \) \(=\) \(\ds \)
\(\ds \leadsto \ \ \) \(\ds \) \(=\) \(\ds \)

So $\map P k \implies \map P {k + 1}$ and the result follows by the Second Principle of Mathematical Induction.


Therefore:

$proposition_n$