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A056987 Discriminants of imaginary quadratic fields with class number 25 (negated). 3
479, 599, 1367, 2887, 3851, 4787, 5023, 5503, 5843, 7187, 7283, 7307, 7411, 8011, 8179, 9227, 9923, 10099, 11059, 11131, 11243, 11867, 12211, 12379, 12451, 12979, 14011, 14923, 15619, 17483, 18211, 19267, 19699, 19891, 20347, 21107, 21323 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Sequence contains 95 members; largest is 93307.

LINKS

Table of n, a(n) for n=1..37.

Eric Weisstein's World of Mathematics, Class Number.

MATHEMATICA

Reap[ For[n = 1, n < 22000, n++, s = Sqrt[-n]; If[ NumberFieldClassNumber[s] == 25, d = -NumberFieldDiscriminant[s]; Print[d]; Sow[d]]]][[2, 1]] // Union (* Jean-Fran├žois Alcover, Oct 05 2012 *)

CROSSREFS

Sequence in context: A252542 A122268 A186950 * A323051 A025025 A108256

Adjacent sequences:  A056984 A056985 A056986 * A056988 A056989 A056990

KEYWORD

nonn,fini

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified November 18 17:21 EST 2019. Contains 329287 sequences. (Running on oeis4.)