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URL: https://oeis.org/A218039

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A218039
Numbers n such that Q(sqrt(n)) has class number 7.
4
577, 1009, 1087, 1294, 1601, 1761, 1934, 2029, 2251, 2302, 2467, 2913, 4139, 4229, 4702, 5039, 5273, 5417, 5743, 5827, 6151, 6598, 7919, 8097, 8311, 8462, 8661, 8773, 9029, 9049, 9101, 9289, 9326, 9539, 10117, 10313, 10357, 10713, 10957, 11021, 11053, 11269
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[11269], SquareFreeQ[#] && NumberFieldClassNumber@Sqrt[#] == 7 &]
PROG
(PARI) is(n)=issquarefree(n) && qfbclassno(if(n%4>1, 4, 1)*n)==7 \\ Charles R Greathouse IV, Jan 19 2017
KEYWORD
nonn
AUTHOR
STATUS
approved