Induction proof: Difference between revisions

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This page explains how to proove with induction method on the natural number with Rodin tools.
This page explains how to prove with induction method on the natural number with Rodin tools.
In other words, how to proove :<br/>
In other words, how to proove :
 
<math>
<math>
P(0)
P(0)
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The proof key is the following theorem:<br/>
The proof key is the following theorem:
 
<math>
<math>
\forall s.s \subseteq \mathbb{N} \land 0 \in s \land  (\forall n.n \in s \Rightarrow n+1 \in s)\Rightarrow  \mathbb{N} \subseteq s
\forall s.s \subseteq \mathbb{N} \land 0 \in s \land  (\forall n.n \in s \Rightarrow n+1 \in s)\Rightarrow  \mathbb{N} \subseteq s
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The proof of the previous theorem is given by instanciate the key theorem with : <math>   \{x|x\in \mathbb{N} \land P(x)\}</math>
The proof of the previous theorem is given by instantiating the key theorem with : <math>   \{x|x\in \mathbb{N} \land P(x)\}</math>
 
[[Category:Proof patterns]]

Revision as of 13:58, 30 October 2008

This page explains how to prove with induction method on the natural number with Rodin tools. In other words, how to proove :


P(0)

\forall i.i \in \mathbb{N}\land P(i) \Rightarrow P(i+1)

\vdash
\forall i. i \in \mathbb{N}  \Rightarrow P(i)


The proof key is the following theorem:


\forall s.s \subseteq \mathbb{N} \land 0 \in s \land  (\forall n.n \in s \Rightarrow n+1 \in s)\Rightarrow  \mathbb{N} \subseteq s


The proof of the previous theorem is given by instantiating the key theorem with : 	  \{x|x\in \mathbb{N} \land P(x)\}