OFFSET
1,1
COMMENTS
Sequence contains 668 terms; largest is 217627.
The class groups associated to 255 of the above discriminants are isomorphic to C_36, 374 have a class group isomorphic to C_18 X C_2, 16 have a class group isomorphic to C_12 X C_3, and the remaining 23 have a class group isomorphic to C_6 X C_6.
LINKS
Andy Huchala, Table of n, a(n) for n = 1..668
Mark Watkins, Class numbers of imaginary quadratic fields, Mathematics of Computation, 73, pp. 907-938.
Eric Weisstein's World of Mathematics, Class Number
PROG
(SageMath)
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)];
[-a[0] for a in ls if a[1] == 36]
CROSSREFS
KEYWORD
nonn,fini,full
AUTHOR
Andy Huchala, Mar 27 2022
STATUS
approved
