A218041 Numbers n such that Q(sqrt(n)) has class number 9.

1129, 1654, 3137, 3719, 4409, 4534, 5521, 5623, 5878, 6809, 7573, 7873, 9998, 10273, 10721, 10814, 11027, 11641, 12323, 12409, 12657, 13069, 13691, 14159, 15374, 15629, 16321, 16382, 17273, 17989, 18633, 19441, 21023, 21781, 22497, 22502, 23003, 23806

Offset

1,1

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Class Number

Mathematica

Select[Range[23806], SquareFreeQ[#] && NumberFieldClassNumber@Sqrt[#] == 9 &]

Prog

(PARI) is(n)=issquarefree(n) && qfbclassno(if(n%4>1, 4, 1)*n)==9 \\ Charles R Greathouse IV, Jan 19 2017

Crossrefs

Cf. A003172, A029702-A029705, A218038-A218040, A218042.

Sequence in context: A198469 A082888 A122384 * A061779 A218159 A325087

Adjacent sequences: A218038 A218039 A218040 * A218042 A218043 A218044

Keyword

nonn

Author

Arkadiusz Wesolowski, Oct 19 2012

Status

approved