CHARACTERIZATION OF INTERSECTING FAMILIES OF MAXIMUM SIZE IN PSL(2, q)
نویسندگان
چکیده
Abstract. We consider the action of the 2-dimensional projective special linear group PSL(2, q) on the projective line PG(1, q) over the finite field Fq, where q is an odd prime power. A subset S of PSL(2, q) is said to be an intersecting family if for any g1, g2 ∈ S, there exists an element x ∈ PG(1, q) such that x1 = x2 . It is known that the maximum size of an intersecting family in PSL(2, q) is q(q − 1)/2. We prove that all intersecting families of maximum size are cosets of point stabilizers for all odd prime powers q > 3.
منابع مشابه
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