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A046005 Discriminants of imaginary quadratic fields with class number 8 (negated). 5
95, 111, 164, 183, 248, 260, 264, 276, 295, 299, 308, 371, 376, 395, 420, 452, 456, 548, 552, 564, 579, 580, 583, 616, 632, 651, 660, 712, 820, 840, 852, 868, 904, 915, 939, 952, 979, 987, 995, 1032, 1043, 1060, 1092, 1128, 1131, 1155, 1195, 1204 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

131 discriminants in this sequence (almost certainly but not proved).

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..131

Steven Arno, M. L. Robinson and Ferrel S. Wheeler, Imaginary quadratic fields with small odd class number, Acta Arithm. 83.4 (1998), 295-330

Duncan A. Buell, Small class numbers and extreme values of L-functions of quadratic fields, Math. Comp., 31 (1977), 786-796.

C. Wagner, Class Number 5, 6 and 7, Math. Comput. 65, 785-800, 1996.

Eric Weisstein's World of Mathematics, Class Number.

Index entries for sequences related to quadratic fields

MATHEMATICA

Union[(-NumberFieldDiscriminant[Sqrt[-#]] &) /@ Select[Range[6400], NumberFieldClassNumber[Sqrt[-#]] == 8 &]] (* Jean-Fran├žois Alcover, Jun 27 2012 *)

PROG

(PARI) ok(n)={isfundamental(-n) && quadclassunit(-n).no == 8} \\ Andrew Howroyd, Jul 20 2018

(Sage) [n for n in (1..6500) if is_fundamental_discriminant(-n) and QuadraticField(-n, 'a').class_number()==8] # G. C. Greubel, Mar 01 2019

CROSSREFS

Cf. A006203, A013658, A014602, A014603, A046002-A046020, A305416.

Cf. A191410.

Sequence in context: A306303 A181767 A331663 * A339522 A045121 A207374

Adjacent sequences:  A046002 A046003 A046004 * A046006 A046007 A046008

KEYWORD

nonn,fini

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified June 13 00:57 EDT 2021. Contains 344980 sequences. (Running on oeis4.)