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A020356 Numbers k such that the continued fraction for sqrt(k) has period 17. 0
157, 241, 313, 449, 829, 857, 941, 1013, 1018, 1193, 1213, 1417, 1565, 1570, 1697, 1994, 2165, 2770, 3065, 3221, 3490, 3533, 3785, 3874, 4210, 4733, 4754, 5081, 5197, 5354, 5450, 5498, 6025, 6274, 6485, 6641, 6653, 6866, 6949, 7010, 7522, 7762, 7949 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..43.

MATHEMATICA

cf17Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Length[ ContinuedFraction[ s][[2]]]]==17]; Select[Range[8000], cf17Q] (* Harvey P. Dale, May 03 2018 *)

CROSSREFS

Sequence in context: A142063 A151739 A142231 * A142367 A216498 A275317

Adjacent sequences: A020353 A020354 A020355 * A020357 A020358 A020359

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified February 6 10:18 EST 2023. Contains 360104 sequences. (Running on oeis4.)