Changed link

Mathematics for Computer Science (November 2013 Version) old link directed to a page that requested password, used a new link that doesn't require one.

free-programming-books.md

@@ -368,7 +368,7 @@
 * [Linear Algebra Done Wrong](http://www.math.brown.edu/~treil/papers/LADW/LADW.pdf) - Sergei Treil
 * [Linear Algebra, Theory And Applications](http://www.math.byu.edu/klkuttle/linearalgebra.pdf) - Kenneth Kuttler
 * [Mathematical Logic - an Introduction](http://www.ii.uib.no/~michal/und/i227/book/book.pdf) (PDF)
-* [Mathematics for Computer Science (November 2013 Version)](http://courses.csail.mit.edu/6.042/fall13/mcs.pdf) (PDF) - Eric Lehman
+* [Mathematics for Computer Science (November 2013 Version)](https://www.cs.princeton.edu/courses/archive/fall13/cos340/LLM.pdf) (PDF) - Eric Lehman
 * [Notes on Differential Equations](http://www.math.cornell.edu/~bterrell/dn.pdf) - Robert E. Terrell
 * [Number Theory](http://web.mit.edu/~holden1/www/math/number-theory.pdf) (PDF)
 * [OpenIntro Statistics](http://www.openintro.org/stat/textbook.php)