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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
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.
MATHEMATICA
Union[(-NumberFieldDiscriminant[Sqrt[-#]] &) /@ Select[Range[6400], NumberFieldClassNumber[Sqrt[-#]] == 8 &]] (* Jean-François 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. A191410.
Sequence in context: A306303 A181767 A331663 * A339522 A045121 A207374
KEYWORD
nonn,fini
AUTHOR
STATUS
approved

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Last modified April 25 07:53 EDT 2024. Contains 371964 sequences. (Running on oeis4.)