Quadratic Residue Covers for Certain Real Quadratic Fields
نویسندگان
چکیده
Let A„{a, b) = {ban+(a-l)/b)2+4an with n > 1 and ¿>|a-l . If W is a finite set of primes such that for each n > 1 there exists some q £W for which the Legendre symbol {A„{a, b)/q) ^ -1 , we call <£ a quadratic residue cover (QRC) for the quadratic fields K„{a, b) = Q{^jA„{a, b)). It is shown how the existence of a QRC for any a, b can be used to determine lower bounds on the class number of K„{a, b) when A„{a, b) is the discriminant of K„{a, b). Also, QRCs are computed for all 1 < a, b < 10000 .
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