Publications of (and about) Paul Erdös
Autor: Erdös, Paul; Fowler, Joel C.; Sós, Vera T.; Wilson, Richard M.
Title: On 2-designs. (In English)
Source: J. Comb. Theory, Ser. A 38, 131-142 (1985).
Review: The set of b for which there exists a linear space with v points and b lines is studied very sharply, particularly for large v and for v of the form n2+n+1. Interesting is an extremal case: if v = n2+n+1, b = n22n+1 the space is obtained from a projective plane replacing one of its lines with a near pencil or a projective plane. Conjectures and problems are given too.
Classif.: * 05B05 Block designs (combinatorics)
05B20 (0,1)-matrices (combinatorics)
51A05 General theory of linear incidence geometry
51E30 Other finite incidence structures
Keywords: linear space; projective plane
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