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A218038 Numbers n such that Q(sqrt(n)) has class number 6. 11
235, 346, 427, 506, 574, 697, 785, 786, 842, 874, 894, 895, 898, 899, 906, 985, 1086, 1191, 1211, 1339, 1342, 1345, 1406, 1527, 1546, 1639, 1735, 1758, 1765, 1851, 1866, 1882, 1937, 1954, 2118, 2230, 2233, 2263, 2298, 2495, 2505, 2510, 2554, 2666, 2678, 2726 (list; graph; refs; listen; history; text; internal format)
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[2726], SquareFreeQ[#] && NumberFieldClassNumber@Sqrt[#] == 6 &]

PROG

(PARI) is(n)=issquarefree(n) && qfbclassno(if(n%4>1, 4, 1)*n)==6 \\ Charles R Greathouse IV, Jan 19 2017

CROSSREFS

Cf. A003172, A029702-A029705, A218039-A218042.

Sequence in context: A036209 A077803 A049857 * A132903 A247474 A147148

Adjacent sequences:  A218035 A218036 A218037 * A218039 A218040 A218041

KEYWORD

nonn

AUTHOR

Arkadiusz Wesolowski, Oct 19 2012

STATUS

approved

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Last modified October 21 11:05 EDT 2019. Contains 328294 sequences. (Running on oeis4.)