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A094613 Fundamental discriminants of real quadratic number fields with class number 4. 3
145, 328, 445, 505, 520, 680, 689, 777, 780, 793, 840, 876, 897, 901, 905, 924, 1020, 1045, 1096, 1105, 1145, 1160, 1164, 1221, 1288, 1292, 1313, 1320, 1365, 1480, 1560, 1640, 1677, 1736, 1740, 1745, 1752, 1820, 1848, 1885, 1932, 2005, 2040, 2056, 2120, 2145 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

Eric Weisstein's World of Mathematics, Class Number

Index entries for sequences related to quadratic fields

MATHEMATICA

Select[Range[2145], NumberFieldDiscriminant@Sqrt[#] == # && NumberFieldClassNumber@Sqrt[#] == 4 &] (* Arkadiusz Wesolowski, Oct 22 2012 *)

CROSSREFS

Cf. A003656, A094619, A094612, A094614, A218156-A218160.

Sequence in context: A176699 A177223 A158133 * A207058 A116208 A211470

Adjacent sequences:  A094610 A094611 A094612 * A094614 A094615 A094616

KEYWORD

nonn

AUTHOR

Eric W. Weisstein, May 14 2004

STATUS

approved

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Last modified June 22 08:02 EDT 2017. Contains 288605 sequences.