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A031815 Period of continued fraction for sqrt(n) contains exactly 47 ones. 0
14899, 32731, 37327, 37391, 43279, 44339, 44407, 51883, 55379, 56291, 58879, 66712, 67024, 68391, 72979, 74639, 76859, 86999, 87599, 89183, 92035, 93631, 96091, 102875, 110723, 111655, 111743, 112591, 113211, 116339, 117367, 118279, 122488 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

MATHEMATICA

cf47Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Count[ContinuedFraction[s][[2]], 1]]==47]; Select[Range[125000], cf47Q] (* Harvey P. Dale, Jan 06 2019 *)

CROSSREFS

Sequence in context: A023045 A186901 A185486 * A235236 A203404 A236352

Adjacent sequences:  A031812 A031813 A031814 * A031816 A031817 A031818

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified July 29 22:13 EDT 2021. Contains 346346 sequences. (Running on oeis4.)