Let K be a subfield of a
cyclotomic extension L of the rational field Q. The Schur subgroup, S(K), of the
Brauer group of K, B(K), consists of those algebra classes which contain an algebra
which is isomorphic to a simple component of a group algebra QG for some finite
group G.
In this paper we describe a set of generators for S(K). We then use this theorem
to determine the 2-primary part of S(K) when L∕K is cyclic and the fourth roots of
unity are not in K.
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