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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 May 16 10:48 EDT 2021. Contains 343941 sequences. (Running on oeis4.)