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A031819 Period of continued fraction for sqrt(n) contains exactly 51 ones. 0
13939, 28531, 40891, 50059, 52264, 55183, 58927, 65656, 66887, 73051, 82519, 94824, 108539, 111896, 113263, 114955, 119743, 131723, 131811, 133867, 147823, 155803, 158299, 161155, 162819, 163283, 169336, 169663, 169675, 176623, 180671, 187039 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..32.

MATHEMATICA

cf51Q[n_]:=Module[{sr=Sqrt[n], x}, x=If[IntegerQ[sr], 1, Count[ ContinuedFraction[ sr][[2]], 1]]; x==51]; Select[Range[200000], cf51Q] (* Harvey P. Dale, Jan 19 2014 *)

CROSSREFS

Sequence in context: A244273 A118464 A031666 * A066939 A215150 A215944

Adjacent sequences:  A031816 A031817 A031818 * A031820 A031821 A031822

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified October 27 10:47 EDT 2021. Contains 348274 sequences. (Running on oeis4.)