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A031808 Period of continued fraction for sqrt(n) contains exactly 40 ones. 0
1999, 2284, 2461, 2644, 2671, 2689, 2956, 2989, 3061, 3661, 3697, 3769, 3817, 4153, 4201, 4987, 4989, 5001, 5101, 5419, 5469, 5647, 5812, 5851, 6067, 6189, 6281, 6331, 6581, 6673, 6689, 6861, 6883, 7078, 7141, 7151, 7261, 7342, 7354, 7661, 7693, 7789 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..42.

MATHEMATICA

cf40Q[n_]:=Module[{s=Sqrt[n]}, !IntegerQ[s]&&Count[ContinuedFraction[s][[2]], 1]==40]; Select[Range[8000], cf40Q] (* Harvey P. Dale, Aug 19 2014 *)

CROSSREFS

Sequence in context: A258106 A253744 A253751 * A167292 A230202 A037029

Adjacent sequences:  A031805 A031806 A031807 * A031809 A031810 A031811

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified August 5 00:15 EDT 2021. Contains 346456 sequences. (Running on oeis4.)