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A046008 Discriminants of imaginary quadratic fields with class number 11 (negated). 4
167, 271, 659, 967, 1283, 1303, 1307, 1459, 1531, 1699, 2027, 2267, 2539, 2731, 2851, 2971, 3203, 3347, 3499, 3739, 3931, 4051, 5179, 5683, 6163, 6547, 7027, 7507, 7603, 7867, 8443, 9283, 9403, 9643, 9787, 10987, 13003, 13267, 14107, 14683, 15667 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..41.

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.

Index entries for sequences related to quadratic fields

MATHEMATICA

Reap[ For[n = 1, n < 15000, n++, s = Sqrt[-n]; If[ NumberFieldClassNumber[s] == 11, d = -NumberFieldDiscriminant[s]; Print[d]; Sow[d]]]][[2, 1]] // Union (* Jean-François Alcover, Oct 05 2012 *)

PROG

(PARI) ok(n)={isfundamental(-n) && quadclassunit(-n).no == 11};

for(n=1, 16000, if(ok(n)==1, print1(n, ", "))) \\ G. C. Greubel, Mar 01 2019

(Sage) [n for n in (1..16000) if is_fundamental_discriminant(-n) and QuadraticField(-n, 'a').class_number()==11] # G. C. Greubel, Mar 01 2019

CROSSREFS

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

Cf. A191410.

Sequence in context: A015992 A065216 A142485 * A009840 A033255 A052233

Adjacent sequences:  A046005 A046006 A046007 * A046009 A046010 A046011

KEYWORD

nonn,fini,full

AUTHOR

Eric W. Weisstein

EXTENSIONS

a(40)-a(41) from Giovanni Resta, Mar 20 2013

STATUS

approved

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Last modified May 26 22:58 EDT 2020. Contains 334634 sequences. (Running on oeis4.)