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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 (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[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

CROSSREFS

Cf. A003172, A029702-A029705, A218038-A218039, A218041-A218042.

Sequence in context: A126897 A296810 A067265 * A158229 A031708 A156814

Adjacent sequences:  A218037 A218038 A218039 * A218041 A218042 A218043

KEYWORD

nonn

AUTHOR

Arkadiusz Wesolowski, Oct 19 2012

STATUS

approved

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Last modified November 16 19:17 EST 2019. Contains 329201 sequences. (Running on oeis4.)