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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.

A351671 Discriminants of imaginary quadratic fields with class number 33 (negated).

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%I A351671 #10 Feb 16 2025 08:34:03
%S A351671 839,1583,1951,2423,3967,4091,4423,4567,4663,4831,4999,5167,5623,5791,
%T A351671 6343,6823,6967,7331,7351,7499,8167,9011,12619,13183,13619,13931,
%U A351671 14251,15299,16619,17419,18691,19163,21347,21563,24019,25411,28027,28163,28579,29243
%N A351671 Discriminants of imaginary quadratic fields with class number 33 (negated).
%C A351671 Sequence contains 101 terms; largest is 222643.
%C A351671 The class group of Q[sqrt(-d)] is isomorphic to C_33 for all d in this sequence.
%H A351671 Andy Huchala, <a href="/A351671/b351671.txt">Table of n, a(n) for n = 1..101</a>
%H A351671 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ClassNumber.html">Class Number</a>
%o A351671 (Sage)
%o A351671 ls = [(QuadraticField(-n, 'a').discriminant(), QuadraticField(-n, 'a').class_number()) for n in (0..10000) if is_fundamental_discriminant(-n) and not is_square(n)];
%o A351671 [-a[0] for a in ls if a[1] == 33]
%Y A351671 Cf. A006203, A013658, A014602, A014603, A046002-A046020, A046125, A056987, A351664.
%K A351671 nonn,fini,full
%O A351671 1,1
%A A351671 _Andy Huchala_, Mar 25 2022