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A060649 Smallest number k==3 (mod 4) such that Q(sqrt(-k)) has class number n. 1
3, 15, 23, 39, 47, 87, 71, 95, 199, 119, 167, 231, 191, 215, 239, 399, 383, 335, 311, 455, 431, 591, 647, 695, 479, 551, 983, 831, 887, 671, 719, 791, 839, 1079, 1031, 959, 1487, 1199, 1439, 1271, 1151, 1959, 1847, 1391, 1319, 2615, 3023, 1751, 1511, 1799 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..50.

Eric Weisstein's World of Mathematics, Class Number.

MATHEMATICA

(* First do <<NumberTheory`NumberTheoryFunctions` *) a=Table[0, {50}]; Do[If[SquareFreeQ[n], c=ClassNumber[ -n]; If[c<=50&&a[[c]]==0, a[[c]]=n]], {n, 3, 3200, 4}]; a

CROSSREFS

Cf. A002148, A081319.

Sequence in context: A106403 A225365 A225060 * A009210 A142882 A161467

Adjacent sequences:  A060646 A060647 A060648 * A060650 A060651 A060652

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Apr 17 2001

EXTENSIONS

Edited by Dean Hickerson, Mar 17 2003

STATUS

approved

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Last modified December 7 14:52 EST 2016. Contains 278877 sequences.