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even & odd
Paul S. Miner writes:
> amrani moussa writes:
>
> > I want to prove that a natural number must be odd? or even? but not the twice in
> > the same time ! But i don't fint the correct instanciation !!!
> > (X(e!1) is a nat !)
> >
> > |-------
> > {1} ((inv(e!1) AND (X(e!1) /= 0)) => ((odd?(X(e!1))) OR (even?(X(e!1)))))
> >
>
> After you expand the definitions of odd? and even?, you can
> instantiate both goal formulae with `floor(X(e!1))'. Then the
^^^^^^^^^^^^^^^
Sorry, that should be `floor(X(e!1)/2)'
> decision procedures should be able to finish off the proof.
>
> --
> -- Paul S. Miner | phone: (757) 864-6201
> -- 1 South Wright St. / MS 130 | fax: (757) 864-4234
> -- NASA Langley Research Center | mailto:p.s.miner@larc.nasa.gov
> -- Hampton, Virginia 23681-2199 | http://shemesh.larc.nasa.gov/~psm/
>
>
- References:
- even & odd
- From: amrani moussa <amranim@ufrima.imag.fr>
- even & odd
- From: "Paul S. Miner" <p.s.miner@larc.nasa.gov>