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A051997
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Consider real quadratic fields of ERD-type with class groups of exponent 2 and discriminants of the form D = r^2*k^2+2k, k odd; sequence gives values of k.
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8
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-1, 1, 1, 3, 1, -1, 1, -3, 1, -1, -5, 3, 1, -1, -3, 3, -5, 1, 5, -3, 3, 7, -1, -1, -3, -5, -1, 1, 5, 1, -7, -1, 7, 1, -5, 1, -1, 3, 5, 1, 3, -3, 13, 5, 3, 1, -15, -5, 3, -7, 7, -3, 3, 13, -3, -11, 3, -15, 1, -1, -21, -33, 15, 3, -3, -5, 5, -17, 7, 3, 5, 1, -5, 7, 3, -13
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OFFSET
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1,4
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COMMENTS
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Excludes discriminants appearing in A051990.
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REFERENCES
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R. A. Mollin, Quadratics, CRC Press, 1996, Appendix A, Table A4(2), column k.
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LINKS
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Table of n, a(n) for n=1..76.
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CROSSREFS
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Cf. A051990, A051991, A051992, A051993, A051994, A051995, A051996, A051998.
Sequence in context: A155828 A226203 A327791 * A155744 A086869 A348953
Adjacent sequences: A051994 A051995 A051996 * A051998 A051999 A052000
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KEYWORD
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sign,fini,full
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AUTHOR
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N. J. A. Sloane, Jan 04 2000
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EXTENSIONS
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Offset changed to 1 by Georg Fischer, Sep 21 2021
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STATUS
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approved
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