OFFSET
1,1
COMMENTS
Sequence contains 109 terms; largest is 296587.
The class group of Q[sqrt(-d)] is isomorphic to C_41 for all d in this sequence.
LINKS
Andy Huchala, Table of n, a(n) for n = 1..109
Mark Watkins, Class numbers of imaginary quadratic fields, Mathematics of Computation, 73, pp. 907-938.
Eric Weisstein's World of Mathematics, Class Number
PROG
(Sage)
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] == 41]
CROSSREFS
KEYWORD
nonn,fini,full
AUTHOR
Andy Huchala, Mar 28 2022
STATUS
approved