A031855 Period of continued fraction for sqrt(n) contains exactly 87 ones.

35179, 51811, 68083, 70723, 75499, 90331, 114211, 117907, 118003, 133651, 138919, 145147, 148231, 156811, 159127, 178471, 181451, 183847, 184471, 191875, 201379, 205099, 212711, 230887, 231016, 231295, 232211, 245335, 252407, 265631, 268087

Offset

1,1

Links

Table of n, a(n) for n=1..31.

Mathematica

cf87Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Count[ContinuedFraction[s][[2]], 1]]==87]; Select[Range[270000], cf87Q] (* Harvey P. Dale, Nov 26 2018 *)

Crossrefs

Sequence in context: A213805 A204491 A085545 * A186567 A235279 A358856

Adjacent sequences: A031852 A031853 A031854 * A031856 A031857 A031858

Keyword

nonn

Author

David W. Wilson

Status

approved