A029705 Squarefree n such that Q(sqrt(n)) has class number 5.

401, 439, 499, 727, 817, 982, 1093, 1126, 1327, 1393, 1429, 1486, 1641, 1766, 1897, 2027, 2081, 2153, 2399, 2878, 3121, 3134, 3181, 3238, 3251, 3253, 3814, 3967, 3997, 4271, 4353, 4357, 4358, 4441, 4591, 4622, 4757, 4889, 5107, 5241, 5269, 5527, 5711, 5774

Offset: 1

Author

Paolo Dominici (pl.dm(AT)libero.it)

Keywords

• nonn

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
• Index entries for sequences related to quadratic fields

Crossrefs

Cf. A003172, A029702-A029704, A218038-A218042.

Programs

Mathematica

Select[Range[5774], SquareFreeQ[#] && NumberFieldClassNumber@Sqrt[#] == 5 &] (* Arkadiusz Wesolowski, Oct 22 2012 *)

PARI

is(n)=issquarefree(n)&&bnfinit('x^2-n).cyc==[5] \\ Charles R Greathouse IV, Oct 18 2012