A046085 - OEIS

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A046085

Numbers n such that Q(sqrt(-n)) has class number 4.

14, 17, 21, 30, 33, 34, 39, 42, 46, 55, 57, 70, 73, 78, 82, 85, 93, 97, 102, 130, 133, 142, 155, 177, 190, 193, 195, 203, 219, 253, 259, 291, 323, 355, 435, 483, 555, 595, 627, 667, 715, 723, 763, 795, 955, 1003, 1027, 1227, 1243, 1387, 1411, 1435, 1507, 1555

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Contains 54 numbers [Arno, Theorem 7], ..., 1387, 1411, 1435, 1507 and 1555. [R. J. Mathar, May 01 2010]

LINKS

Table of n, a(n) for n=1..54.

Steven Arno, The imaginary quadratic fields of class number 4, Acta Arithm. vol 60 issue 4 (1991).

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

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

Eric Weisstein's World of Mathematics, Pythagorean Triple.

Index entries for sequences related to quadratic fields

PROG

(PARI) \\ See A005847

CROSSREFS

See A003173, A005847, A006203, A046085, A046002, A055109, A046004, A055110, A046006, A055111 for class numbers 1 through 10.

Sequence in context: A152010 A352381 A243750 * A054296 A155704 A105189

Adjacent sequences: A046082 A046083 A046084 * A046086 A046087 A046088

KEYWORD

nonn,fini,full

AUTHOR

N. J. A. Sloane, Jun 16 2000

STATUS

approved