Bounds for the characteristic rank and cup-length of oriented Grassmann manifolds
نویسندگان
چکیده
منابع مشابه
Application of Gröbner Bases to the Cup-length of Oriented Grassmann Manifolds
Let R be a commutative ring. The cup-length of R is defined by the greatest number n such that there exist x1, . . . , xn ∈ R \ R with x1 · · · xn , 0. We denote the cup-length of R by cup(R). In particular, for a space X and a commutative ring A, the cup-length of X with the coefficient A, is defined by cup(H̃(X; A)). We denote it by cupA(X). It is well-known that cupA(X) is a lower bound for t...
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ژورنال
عنوان ژورنال: Archivum Mathematicum
سال: 2018
ISSN: 0044-8753,1212-5059
DOI: 10.5817/am2018-5-313