A020352 Numbers k such that the continued fraction for sqrt(k) has period 13.

193, 281, 481, 565, 593, 746, 778, 997, 1082, 1138, 1250, 1514, 1930, 2042, 2426, 2477, 2837, 2930, 3121, 3145, 3338, 3413, 3625, 3797, 3853, 3925, 4001, 4058, 4421, 4745, 5122, 5234, 5741, 6010, 6170, 6481, 7025, 7250, 7418, 7730, 7757, 7877, 7930, 8450

Offset

1,1

Links

Table of n, a(n) for n=1..44.

Mathematica

cf13Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Length[ContinuedFraction[s][[2]]]==13]]; Select[ Range[9000], cf13Q] (* Harvey P. Dale, Aug 07 2023 *)

Crossrefs

Sequence in context: A226147 A142925 A060333 * A146338 A201858 A146360

Adjacent sequences: A020349 A020350 A020351 * A020353 A020354 A020355

Keyword

nonn

Author

David W. Wilson

Status

approved