A020390 - OEIS

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A020390

Numbers k such that the continued fraction for sqrt(k) has period 51.

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

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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: A282015 A367735 A217656 * A156620 A214116 A221451

Adjacent sequences: A020387 A020388 A020389 * A020391 A020392 A020393

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved