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A081319 Smallest squarefree integer k such that Q(sqrt(-k)) has class number n. 5
1, 5, 23, 14, 47, 26, 71, 41, 199, 74, 167, 89, 191, 101, 239, 146, 383, 293, 311, 194, 431, 269, 647, 329, 479, 314, 983, 341, 887, 461, 719, 446, 839, 614, 1031, 626, 1487, 1199, 1439, 689, 1151, 794, 1847, 854, 1319, 941, 3023, 1106, 1511, 1109, 1559 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert G. Wilson v, Table of n, a(n) for n = 1..4500

Duncan A. Buell, Small class numbers and extreme values of L-functions of quadratic fields, Math. Comp., 31 (1977), 786-796.

MATHEMATICA

t[_] := 0; k = -1; While[k > -3100, a = NumberFieldClassNumber@Sqrt@k; If[t[a] == 0, t[a] = -k; Print[{a, -k}]]; k--]; t /@ Range@51 (* Robert G. Wilson v, Sep 25 2017 *)

CROSSREFS

Cf. A060649, A038552, A046125, A014602-A046020.

Sequence in context: A054415 A156328 A078190 * A177242 A233756 A002582

Adjacent sequences:  A081316 A081317 A081318 * A081320 A081321 A081322

KEYWORD

nonn

AUTHOR

Dean Hickerson, Mar 18 2003

EXTENSIONS

Edited by Max Alekseyev, Apr 28 2010

STATUS

approved

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Last modified February 28 06:55 EST 2020. Contains 332321 sequences. (Running on oeis4.)