cp's OEIS Frontend

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.

A351675 Discriminants of imaginary quadratic fields with class number 37 (negated).

This page as a plain text file.
%I A351675 #12 Feb 16 2025 08:34:03
%S A351675 1487,2447,3391,5839,6367,8147,9803,10739,12343,12583,12967,14767,
%T A351675 15259,16927,18947,19403,20011,20147,21139,21587,22807,23371,23627,
%U A351675 26731,28283,28307,31699,31723,36691,37171,37243,38371,39139,39451,40531,41659,42283,42443
%N A351675 Discriminants of imaginary quadratic fields with class number 37 (negated).
%C A351675 Sequence contains 85 terms; largest is 158923.
%C A351675 The class group of Q[sqrt(-d)] is isomorphic to C_37 for all d in this sequence.
%H A351675 Andy Huchala, <a href="/A351675/b351675.txt">Table of n, a(n) for n = 1..85</a>
%H A351675 Mark Watkins, <a href="https://doi.org/10.1090/S0025-5718-03-01517-5">Class numbers of imaginary quadratic fields</a>, Mathematics of Computation, 73, pp. 907-938.
%H A351675 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ClassNumber.html">Class Number</a>
%o A351675 (Sage)
%o A351675 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 A351675 [-a[0] for a in ls if a[1] == 37]
%Y A351675 Cf. A006203, A013658, A014602, A014603, A046002-A046020, A046125, A056987, A351664-A351680.
%K A351675 nonn,fini,full
%O A351675 1,1
%A A351675 _Andy Huchala_, Mar 27 2022