sympy/sympy — pull request #1387 by mrocklin (2012-06-25 19:42:25+00:00)
Title: Intersect range

Integers.intersect(Interval) now produces a Range rather than a FiniteSet
Integers.intersect(Interval) produces an unevaluated Intersection when the Interval is unbounded

Fixes issue
http://code.google.com/p/sympy/issues/detail?id=3301