Abstract
A Cameron-Liebler line class is a set L of lines in PG(3, q) for which there exists a number x such that |L⋂S|=x for all spreads S. There are many equivalent properties: Theorem 1 lists eight. This paper classifies Cameron-Liebler line classes with x⩽4 (with two exceptions). It is also shown that the study of Cameron-Liebler line classes is equivalent to the study of weighted sets of points in PG(3, q) with two weights on lines.
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Penttila, T. Cameron-Liebler line classes in PG (3,q). Geom Dedicata 37, 245–252 (1991). https://doi.org/10.1007/BF00181401
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DOI: https://doi.org/10.1007/BF00181401