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A218040
Numbers n such that Q(sqrt(n)) has class number 8.
4
226, 399, 442, 646, 799, 870, 910, 994, 1023, 1122, 1155, 1239, 1290, 1299, 1351, 1443, 1446, 1590, 1705, 1743, 1785, 1914, 1947, 1995, 2010, 2019, 2035, 2134, 2210, 2211, 2310, 2379, 2402, 2410, 2415, 2434, 2451, 2482, 2490, 2605, 2705, 2706, 2730, 2739, 2751
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[2751], SquareFreeQ[#] && NumberFieldClassNumber@Sqrt[#] == 8 &]
PROG
(PARI) is(n)=issquarefree(n) && qfbclassno(if(n%4>1, 4, 1)*n)==8 \\ Charles R Greathouse IV, Jan 19 2017
KEYWORD
nonn
AUTHOR
STATUS
approved