Countable subspaces
نویسندگان
چکیده
منابع مشابه
Closed Ideals of Operators on and Complemented Subspaces of Banach Spaces of Functions with Countable Support
Let λ be an infinite cardinal number and let `∞(λ) denote the subspace of `∞(λ) consisting of all functions which assume at most countably many non zero values. We classify all infinite dimensional complemented subspaces of `∞(λ), proving that they are isomorphic to `∞(κ) for some cardinal number κ. Then we show that the Banach algebra of all bounded linear operators on `∞(λ) or `∞(λ) has the u...
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Lower and upper bounds on the size of a covering of subspaces in the Grassmann graph Gq(n, r) by subspaces from the Grassmann graph Gq(n, k), k ≥ r , are discussed. The problem is of interest from four points of view: coding theory, combinatorial designs, q-analogs, and projective geometry. In particular we examine coverings based on lifted maximum rank distance codes, combined with spreads and...
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ژورنال
عنوان ژورنال: Indagationes Mathematicae (Proceedings)
سال: 1970
ISSN: 1385-7258
DOI: 10.1016/s1385-7258(70)80022-1