A020426 Numbers k such that the continued fraction for sqrt(k) has period 87.

3049, 3769, 7261, 8053, 8485, 8746, 13553, 15233, 17785, 19226, 19585, 20029, 20149, 20897, 20921, 21929, 22037, 22585, 25681, 26977, 29497, 31069, 31253, 32666, 33113, 33874, 36473, 38245, 38393, 38861, 40193, 41333, 42202, 42829, 43117, 44845, 45098

Offset

1,1

Links

Table of n, a(n) for n=1..37.

Mathematica

cf87Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Length[ ContinuedFraction[ s][[2]]]]==87]; Select[Range[46000], cf87Q] (* Harvey P. Dale, Jun 04 2019 *)

Crossrefs

Sequence in context: A035776 A108000 A232575 * A101806 A038014 A005944

Adjacent sequences: A020423 A020424 A020425 * A020427 A020428 A020429

Keyword

nonn

Author

David W. Wilson

Status

approved