Thu, 01 Sep 2011 23:18:34 +0000 urbanc included Higman's lemma from the Isabelle repository
Thu, 01 Sep 2011 20:26:30 +0000 urbanc solved the SUBSEQ/SUPSEQ problem
(0) -100 -30 -10 -2 +2 +10 +30 +100 tip