Index: pseries.cpp
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RCS file: /home/cvs/GiNaC/ginac/pseries.cpp,v
retrieving revision 1.78
diff -r1.78 pseries.cpp
960c960
< 	if (!must_expand_basis && !basis.subs(r, subs_options::no_pattern).is_zero())
---
> 	if (!must_expand_basis && !basis.subs(r, subs_options::no_pattern).is_zero() && !is_a<add>(basis))