ON SOME REGULAR MULTI-VEBLEN CONFIGURATIONS, THE GEOMETRY OF COMBINATORIAL QUASI GRASSMANNIANS
نویسندگان
چکیده
منابع مشابه
Combinatorial Grassmannians
We follow the rules: k, n denote elements of N and X, Y , Z denote sets. One can prove the following propositions: (1) For all sets a, b such that a 6= b and a = n and b = n holds a ∩ b < n and n+ 1 ≤ a ∪ b. (2) For all sets a, b such that a = n+ k and b = n+ k holds a ∩ b = n iff a ∪ b = n+ 2 · k. (3) X ≤ Y iff there exists a function f such that f is one-to-one and X ⊆ dom f and f ◦X ⊆ Y. (4)...
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ژورنال
عنوان ژورنال: Demonstratio Mathematica
سال: 2009
ISSN: 2391-4661
DOI: 10.1515/dema-2009-0216