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A020390 Numbers k such that the continued fraction for sqrt(k) has period 51. 0
1201, 1933, 2017, 2437, 2953, 3037, 5189, 5657, 6353, 6865, 7793, 8237, 8513, 8665, 10522, 10546, 10861, 10897, 11962, 12373, 14657, 15077, 15346, 15802, 16138, 16393, 16405, 16690, 16945, 17585, 18097, 18362, 19345, 19466, 20722, 21493, 22717, 22765 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..38.

MATHEMATICA

cfp51Q[n_]:=Module[{s=Sqrt[n]}, !IntegerQ[s]&&Length[ContinuedFraction[s][[2]]]==51]; Select[Range[23000], cfp51Q] (* Harvey P. Dale, Aug 27 2014 *)

CROSSREFS

Cf. A003285.

Sequence in context: A268877 A282015 A217656 * A156620 A214116 A221451

Adjacent sequences:  A020387 A020388 A020389 * A020391 A020392 A020393

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified December 7 07:01 EST 2021. Contains 349567 sequences. (Running on oeis4.)