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A014603 Discriminants of imaginary quadratic fields with class number 2 (negated). 24
15, 20, 24, 35, 40, 51, 52, 88, 91, 115, 123, 148, 187, 232, 235, 267, 403, 427 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Includes only fundamental discriminants. The list of non-fundamental imaginary quadratic discriminants with class number 2 (negated) is 32, 36, 48, 60, 64, 72, 75, 99, 100, 112, 147. [From Andrew V. Sutherland, Apr 08 2010]

REFERENCES

H. Cohen, Course in Computational Alg. No. Theory, Springer, 1993, p. 229.

LINKS

Table of n, a(n) for n=0..17.

A. Abatzoglou, A. Silverberg, A. V. Sutherland, A, Wong, A framework for deterministic primality proving using elliptic curves with complex multiplication, arXiv preprint arXiv:1404.0107, 2014

Rick L. Shepherd, Binary quadratic forms and genus theory, Master of Arts Thesis, University of North Carolina at Greensboro, 2013

Eric Weisstein's World of Mathematics, Class Number.

Index entries for sequences related to quadratic fields

MATHEMATICA

Union[ (-NumberFieldDiscriminant[ Sqrt[-#]] &) /@ Select[ Range[500], NumberFieldClassNumber[ Sqrt[-#]] == 2 &]] (* Jean-Fran├žois Alcover, Jan 04 2012 *)

CROSSREFS

Cf. A006203, A013658, A014602, A046002, ..., A046020.

Sequence in context: A214410 A102495 A133288 * A070222 A143321 A066860

Adjacent sequences:  A014600 A014601 A014602 * A014604 A014605 A014606

KEYWORD

nonn,fini,full,nice

AUTHOR

Eric Rains (rains(AT)caltech.edu)

STATUS

approved

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Last modified November 21 16:08 EST 2017. Contains 295003 sequences.