| 96 |      1 | <HTML>
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|  |      2 | <HEAD>
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|  |      3 |    <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
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|  |      4 |    <TITLE>G4ip Prover</TITLE>
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|  |      5 | </HEAD>
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|  |      6 | <BODY TEXT="#000000" BGCOLOR="#C7C3C7" LINK="#0000EF" VLINK="#51188E" ALINK="#FF0000">
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|  |      7 | 
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|  |      8 | <H2>Prover for G4ip (LJT)  </H2>
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|  |      9 | 
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|  |     10 | <A HREF="README">Readme</A>
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|  |     11 | 
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|  |     12 | 
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|  |     13 | <HR>
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|  |     14 | <B>Formulae:</B>    
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|  |     15 |     F ::= <CODE>false</CODE> 
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|  |     16 |     | A 
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|  |     17 |     | F <CODE>&</CODE> F 
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|  |     18 |     | F <CODE>v</CODE> F 
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|  |     19 |     | F <CODE>-></CODE> F 
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|  |     20 |     | F <CODE><-></CODE> F
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|  |     21 |     | (F)<BR>
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|  |     22 | <B>Sequents:</B>     <CODE>=></CODE> F     or 
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|  |     23 |                      [F,]* F <CODE>=></CODE> F
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|  |     24 | 
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|  |     25 | <HR>
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|  |     26 | <B>Inference Rules:</B> 
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|  |     27 | <A HREF="G4ip.html">html</A>,
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|  |     28 | <A HREF="G4ip.dvi">dvi</A> or 
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|  |     29 | <A HREF="G4ip.ps">ps</A>.
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|  |     30 | 
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|  |     31 | <HR>
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|  |     32 | <B>Start:</B> starts the proof search, 
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|  |     33 | <B>Clear:</B> clears the text fields,<BR>
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|  |     34 | <B>Next:</B>  searches for the next proof,
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|  |     35 | <B>Stop:</B>  stops the proof search.
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|  |     36 | 
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|  |     37 | <HR>
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|  |     38 | <!-- APPLET code="G4ip/ProverApplet.class" width=600 height=100 -->
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|  |     39 | <APPLET code="G4ip/ProverApplet.class" archive="G4ip/ProverApplet.jar" width=600 height=100>
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|  |     40 | <PARAM name="LHS_size" value="22">
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|  |     41 | <PARAM name="RHS_size" value="37">
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|  |     42 | </APPLET>
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|  |     43 | 
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|  |     44 | 
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|  |     45 | <HR>
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|  |     46 | <B>Provable Examples:</B>
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|  |     47 | <TT>
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|  |     48 | <DL>
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|  |     49 | <DD>             => (p v (q v r)) <-> ((p v q) v r)</DD>
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|  |     50 | <DD>             => (p & (q & r)) <-> ((p & q) & r)</DD>
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|  |     51 | <DD>             => (p & (q v r)) <-> ((p & q) v (p & r))</DD>
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|  |     52 | <DD>             => (p v (q & r)) <-> ((p v q) & (p v r))</DD>
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|  |     53 | <DD>             => (p -> p) -> (p -> p)</DD>
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|  |     54 | <DD>             => (a -> (b -> c)) -> ((a -> b) -> (a -> c))</DD>
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|  |     55 | <DD>             => a -> ((a -> b) -> a)</DD>
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|  |     56 | <DD>             => b -> ((a -> b) -> b)</DD>
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|  |     57 | <DD>             => (a & b) -> (b & a)</DD>
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|  |     58 | <DD>             => (a -> (a -> b)) -> (a -> b)</DD>
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|  |     59 | <DD>             => ((((p -> q) -> p) -> p) -> q) -> q</DD>
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|  |     60 | <DD>             => (a v (a -> b)) -> (((a -> b) -> a)-> a)</DD>
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|  |     61 | <DD>             => (a -> (b -> false)) -> (b -> (a -> false))</DD>
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|  |     62 | <DD>             => ((a v (a -> false))-> false)-> false</DD>
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|  |     63 | <DD>a & b, c & d => b & c</DD>
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|  |     64 | <DD>(a v (a-> false)) -> false => false</DD>
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|  |     65 | </DL>
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|  |     66 | </TT>
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|  |     67 | 
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|  |     68 | <B>Non-Provable Examples:</B>
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|  |     69 | <TT>
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|  |     70 | <DL>
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|  |     71 | <DD>             => ((a -> b) -> a) -> a</DD>
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|  |     72 | <DD>             => a v (a -> false)</DD>
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|  |     73 | <DD>             => (a & b v (((( a-> flase) -> false) -> q) v (b -> q)) -> q) -> q</DD>
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|  |     74 | </DL>
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|  |     75 | </TT>
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|  |     76 | 
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|  |     77 | 
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|  |     78 | <A HREF="fun.html">Some advanced examples</A>
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|  |     79 | 
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|  |     80 | <HR>
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|  |     81 | <B>Source Code:</B>
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|  |     82 | <A HREF="Formulae.pizza">Formulae</A>,
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|  |     83 | <A HREF="Contexts.pizza">Contexts</A>,
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|  |     84 | <A HREF="Sequents.pizza">Sequents</A>,
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|  |     85 | <A HREF="ProofDisplay.pizza">ProofDisplay</A>,
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|  |     86 | <A HREF="Prover.pizza">Prover</A>,
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|  |     87 | <A HREF="Parser.pizza">Parser</A>,
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|  |     88 | <A HREF="ProverApplet.pizza">Applet</A><BR>
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|  |     89 | 
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|  |     90 | 
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|  |     91 | <HR>
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|  |     92 | <B>Lambda Prolog Version:</B> The programm 
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|  |     93 | <A HREF="G4ip.mod">G4ip.mod</A> can be executed using  
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|  |     94 | <A HREF="http://www.cis.upenn.edu/~dale/lProlog/terzo/index.html">Terzo</A>
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|  |     95 | Another implementation of G4ip by Joshua Hodas and Dale Miller written in 
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|  |     96 | <A HREF="http://www.cs.hmc.edu/~hodas/research/lolli/">Lolli</a> can be found
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|  |     97 | <A HREF="ftp://ftp.cse.psu.edu/pub/dale/ic94-code/index.html">here</A>.
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|  |     98 | 
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|  |     99 | 
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|  |    100 | <HR>
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|  |    101 | <ADDRESS>
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|  |    102 | <A HREF="mailto:Christian.Urban@cl.cam.ac.uk">Christian Urban</A></ADDRESS>
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|  |    103 | 
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|  |    104 | 
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|  |    105 | <P><!-- Created: Tue Mar  4 00:23:25 GMT 1997 -->
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|  |    106 | <!-- hhmts start -->
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|  |    107 | Last modified: Sun May 10 18:18:28 GMT 1998
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|  |    108 | <!-- hhmts end -->
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|  |    109 | </BODY>
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|  |    110 | </HTML>
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