The following applies to all texts in this directory. Copyright (c) 2007 David Anthony SANTOS. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. Details of the GNU FDL can be found here: http://www.gnu.org/licenses/licenses.html The graphics file tower-of-hanoi2.eps is a photograph taken by David Joyner in November 2008 and I hearby release it into the public domain. It is included in discrete_math_lecture_notes2.pdf. Added 2012-06-26: I have just learned of the passing of David Santos. I don't know the date but he died in Philadelpia in unusual circumstances sometime in 2011. I have also uploaded his PhD thesis, written in 1993 under the direction of Prof. Hugh Montgomery at the University of Michigan. He was known as an inspirational teacher and a prolific author of high quality textbooks (most of which have been posted here). For years, he maintained openmathtexts.org, which maintained a list of open source textbooks in mathematics. RIP