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 A046004 Discriminants of imaginary quadratic fields with class number 7 (negated). 8
 71, 151, 223, 251, 463, 467, 487, 587, 811, 827, 859, 1163, 1171, 1483, 1523, 1627, 1787, 1987, 2011, 2083, 2179, 2251, 2467, 2707, 3019, 3067, 3187, 3907, 4603, 5107, 5923 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS 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. Eric Weisstein's World of Mathematics, Class Number. MATHEMATICA Union[(-NumberFieldDiscriminant[Sqrt[-#]] &) /@ Select[Range[6000], NumberFieldClassNumber[Sqrt[-#]] == 7 &]] (* Jean-François Alcover, Jun 27 2012 *) PROG (PARI) ok(n)={isfundamental(-n) && quadclassunit(-n).no == 7}; for(n=1, 6000, if(ok(n)==1, print1(n, ", "))) \\ G. C. Greubel, Mar 01 2019 (Sage) [n for n in (1..6000) if is_fundamental_discriminant(-n) and QuadraticField(-n, 'a').class_number()==7] # G. C. Greubel, Mar 01 2019 CROSSREFS Cf. A006203, A013658, A014602, A014603, A046002-A046020. Cf. A191410. Sequence in context: A157921 A033224 A142178 * A044322 A044703 A142277 Adjacent sequences:  A046001 A046002 A046003 * A046005 A046006 A046007 KEYWORD nonn,fini,full AUTHOR STATUS approved

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Last modified May 26 09:37 EDT 2020. Contains 334620 sequences. (Running on oeis4.)