This file records noteworthy changes.
+1.7.11 (3 August 2020)
+* Fix elusive bugs in factor() and in expand().
+
+1.7.10 (28 June 2020)
+* Fix collect_common_factors() for hidden zero arguments.
+* Fix build on modern systems (C++20 and Python3).
+
1.7.9 (11 April 2020)
* Fix unarchiving of overloaded functions.
* Fix MinGW64 build.