A031858 Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 90 ones.

9949, 10651, 11131, 11614, 12511, 13159, 14431, 14479, 14557, 14974, 15679, 16486, 17086, 18244, 19249, 19849, 20989, 21019, 21217, 21849, 23158, 23781, 23869, 24511, 24652, 25089, 25117, 25468, 26188, 27337, 27549, 27967, 28129, 28591, 28597, 30718

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

q[k_] := Module[{c = ContinuedFraction[Sqrt[k]]}, Length[c] == 2 && Count[c[[2]], 1] == 90]; Select[Range[30000], q] (* Amiram Eldar, Aug 14 2025 *)

Crossrefs

Sequence in context: A031856 A252573 A266917 * A254975 A182696 A126978

Adjacent sequences: A031855 A031856 A031857 * A031859 A031860 A031861

Keyword

nonn

Author

David W. Wilson

Status

approved