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Line-closed combinatorial geometries - MaRDI portal

Line-closed combinatorial geometries (Q1088668)

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scientific article; zbMATH DE number 3991520
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Line-closed combinatorial geometries
scientific article; zbMATH DE number 3991520

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    Line-closed combinatorial geometries (English)
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    1987
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    We present some results on combinatorial geometries (geometric lattices) in which closure is line-closure. We prove that every interval of a line- closed geometry is line-closed. Furthermore, if every rank 3 interval of a geometry is line-closed, then the geometry is line-closed. This implies that every supersolvable geometry is line-closed. Though not true in general, supersolvability does characterize the line-closed graphic geometries.
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    combinatorial geometries
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    geometric lattices
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