论文信息 - Modularity of tangential k-blocks

Modularity of tangential k-blocks

This paper examines the role of modularity in tangential k-blocks over GF(9). It is shown that if M is a tangential k-block over GF(9) and F is a modular flat of M which is aftine over GF(9) then the simple matroid associated with the complete Brown truncation of A4 by F is also a tangential k-block over GF(9). This enables us to construct tangential k-blocks over GF(9) of all ranks Y where 9’ - 9 + 2 < r< 9k. We also consider tangential k-blocks which have modular hyperplanes; bounds are placed on the rank of members of this class and some of their minors are exhibited.

Geoff Whittle

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