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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A046085 Numbers n such that Q(sqrt(-n)) has class number 4.

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%I A046085 #27 Feb 16 2025 08:32:38
%S A046085 14,17,21,30,33,34,39,42,46,55,57,70,73,78,82,85,93,97,102,130,133,
%T A046085 142,155,177,190,193,195,203,219,253,259,291,323,355,435,483,555,595,
%U A046085 627,667,715,723,763,795,955,1003,1027,1227,1243,1387,1411,1435,1507,1555
%N A046085 Numbers n such that Q(sqrt(-n)) has class number 4.
%C A046085 Contains 54 numbers [Arno, Theorem 7], ..., 1387, 1411, 1435, 1507 and 1555. [_R. J. Mathar_, May 01 2010]
%H A046085 Steven Arno, <a href="http://matwbn.icm.edu.pl/ksiazki/aa/aa60/aa6042.pdf">The imaginary quadratic fields of class number 4</a>, Acta Arithm. vol 60 issue 4 (1991).
%H A046085 Steven Arno, M. L. Robinson, Ferrell S. Wheeler, <a href="http://matwbn.icm.edu.pl/ksiazki/aa/aa83/aa8341.pdf">Imaginary quadratic fields with small odd class number</a>, Acta Arith. 83 (1998) 295-330.
%H A046085 Keith Matthews, <a href="http://www.numbertheory.org/classnos/">Tables of imaginary quadratic fields with small class numbers</a>
%H A046085 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PythagoreanTriple.html">Pythagorean Triple.</a>
%H A046085 <a href="/index/Qua#quadfield">Index entries for sequences related to quadratic fields</a>
%o A046085 (PARI) \\ See A005847
%Y A046085 See A003173, A005847, A006203, A046085, A046002, A055109, A046004, A055110, A046006, A055111 for class numbers 1 through 10.
%K A046085 nonn,fini,full
%O A046085 1,1
%A A046085 _N. J. A. Sloane_, Jun 16 2000