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A051994 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 r. 0
6, 7, 8, 3, 10, 11, 11, 4, 12, 14, 3, 5, 16, 17, 6, 6, 4, 20, 4, 7, 7, 3, 22, 23, 8, 5, 25, 25, 5, 26, 4, 28, 4, 29, 6, 30, 32, 11, 7, 36, 12, 13, 3, 8, 14, 44, 3, 9, 16, 7, 7, 17, 17, 4, 18, 5, 19, 4, 61, 62, 3, 2, 5, 26, 27, 17, 20, 6, 16, 39, 28, 146, 30, 23, 61, 22 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Excludes discriminants appearing in A051990.

REFERENCES

R. A. Mollin, Quadratics, CRC Press, 1996, Appendix A, Table A4.

LINKS

Table of n, a(n) for n=0..75.

CROSSREFS

Cf. A051990-A051998.

Sequence in context: A256922 A202346 A117022 * A085661 A265276 A286474

Adjacent sequences:  A051991 A051992 A051993 * A051995 A051996 A051997

KEYWORD

nonn,fini

AUTHOR

N. J. A. Sloane, Jan 04 2000

STATUS

approved

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Last modified October 28 18:25 EDT 2020. Contains 338064 sequences. (Running on oeis4.)