R><PRE><B>void check_parents_and_uplinks_in_proof(Plist proof);
</B></PRE><A NAME="copy_and_renumber_proof"></A><HR><PRE><B>Plist copy_and_renumber_proof(Plist proof, int start);
</B></PRE>We assume that every clause occurs after its parents.
<A NAME="expand_proof"></A><HR><PRE><B>Plist expand_proof(Plist proof, I3list *pmap);
</B></PRE>Given a proof, return a more detailed proof, entirely new, leaving the
given proof unchanged.  Also returned is an I3list mapping new IDs to
pairs <old_id, n>.  The n compne