This directory contains errata lists for the book Concrete Mathematics by Graham, Knuth, and Patashnik. You can more-or-less read them without running them through TeX. But if you want pretty-printed output, you need the file gkpmac.tex (which is on ~ftp/pub/tex/local/lib) and you may also need to make fonts with METAFONT, using sources found on ~ftp/pub/tex/local/cm (the Concrete Roman and Italic fonts) and on ~ftp/pub/tex/ams/amsfonts/sources/euler (the AMS Euler fonts). File err1.tex contains changes to the first printing, err2.tex contains changes to the second printing, etc.