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A046003 Discriminants of imaginary quadratic fields with class number 6 (negated). 2
87, 104, 116, 152, 212, 244, 247, 339, 411, 424, 436, 451, 472, 515, 628, 707, 771, 808, 835, 843, 856, 1048, 1059, 1099, 1108, 1147, 1192, 1203, 1219, 1267, 1315, 1347, 1363, 1432, 1563, 1588, 1603, 1843, 1915, 1963, 2227, 2283, 2443, 2515, 2563, 2787, 2923, 3235, 3427, 3523, 3763 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

Steven Arno, M. L. Robinson, Ferrell S. Wheeler, Imaginary quadratic fields with small odd class number, Acta Arith. 83 (1998) 295-330.

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

Keith Matthews, Tables of imaginary quadratic fields with small class numbers.

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

Mark Watkins, Class numbers of imaginary quadratic fields, Mathematics of Computation, 73, pp. 907-938

Eric Weisstein's World of Mathematics, Class Number.

Index entries for sequences related to quadratic fields

MATHEMATICA

Union[(-NumberFieldDiscriminant[Sqrt[-#]] &) /@ Select[Range[3800], NumberFieldClassNumber[Sqrt[-#]] == 6 &]] (* Jean-Fran├žois Alcover, Jun 27 2012 *)

PROG

(PARI) ok(n)={isfundamental(-n) && quadclassunit(-n).no == 6};

for(n=1, 4000, if(ok(n)==1, print1(n, ", "))) \\ G. C. Greubel, Mar 01 2019

(Sage) [n for n in (1..4000) if is_fundamental_discriminant(-n) and QuadraticField(-n, 'a').class_number()==6] # G. C. Greubel, Mar 01 2019

CROSSREFS

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

Cf. A191410.

Sequence in context: A256083 A038005 A305266 * A095567 A205672 A039489

Adjacent sequences:  A046000 A046001 A046002 * A046004 A046005 A046006

KEYWORD

nonn,fini,full

AUTHOR

Eric W. Weisstein

EXTENSIONS

More terms from Seiichi Manyama, Jun 03 2018

STATUS

approved

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Last modified November 18 04:44 EST 2019. Contains 329248 sequences. (Running on oeis4.)