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Intersection cohomology of reductive varieties. (English) Zbl 1129.14033
Summary: We extend the methods developed in our earlier work to algorithmically compute the intersection cohomology Betti numbers of reductive varieties. These form a class of highly symmetric varieties that includes equivariant compactifications of reductive groups. Thereby, we extend a well-known algorithm for toric varieties.

##### MSC:
 14F43 Other algebro-geometric (co)homologies (e.g., intersection, equivariant, Lawson, Deligne (co)homologies) 14M25 Toric varieties, Newton polyhedra, Okounkov bodies 19D99 Higher algebraic $$K$$-theory 55N33 Intersection homology and cohomology in algebraic topology
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