A031808 Period of continued fraction for sqrt(n) contains exactly 40 ones.

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

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