<HTML><HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> <TITLE>Advanced Examples</TITLE></HEAD><BODY TEXT="#000000" BGCOLOR="#C7C3C7" LINK="#0000EF" VLINK="#51188E" ALINK="#FF0000"><H2>Some Advanced Examples </H2>Be cautious: some of the following formulae have big proofs!<HR><TT><DL><DD> => (((a & b) v (a->f) v (b->f))->f)->f</DD><DD> => (a & b & c v ((a->f) v (b->f) v (c->f))->f)->f</DD><DD> => d&(b->b->a)&(c->c->b)&(d->d->c)->a</DD></DL></TT><HR><ADDRESS><A HREF="mailto:Christian.Urban@cl.cam.ac.uk">Christian Urban</A></ADDRESS><P><!-- Created: Tue Mar 4 00:23:25 GMT 1997 --><!-- hhmts start -->Last modified: Sun Nov 23 20:20:31 GMT 1997<!-- hhmts end --></BODY></HTML>