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A031855 Period of continued fraction for sqrt(n) contains exactly 87 ones. 0
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 (list; graph; refs; listen; history; text; internal format)
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 A133282

Adjacent sequences:  A031852 A031853 A031854 * A031856 A031857 A031858

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified June 20 17:43 EDT 2019. Contains 324234 sequences. (Running on oeis4.)