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Doubly Reversed Flag

Finally we show   (rev rev F) R F   .

We want to prove
( F  : Flag  ) (rev (rev F)) R F .
We take the following steps:

And thus the main goal is proved.


1. Because the formula to be proved is universally quantified, our first step is to eliminate the quantifier, by introducing a new constant, f of sort Flag, to stand for the variable F .

2. After adding "= true " as its right side, and substituting  f for F, what remains to be proved is the equation

(rev rev f R f) = true .
For this, we use reduction, applying the current set of rewrite rules to each side, to see if these two terms reduce to the same thing, which they do.

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       This page was generated by Kumo on Tue Feb 13 17:33:10 PST 2001.