A031813 Period of continued fraction for sqrt(n) contains exactly 45 ones.

20875, 25559, 25591, 32875, 39447, 50879, 51847, 57955, 62419, 70599, 70871, 75947, 77087, 78055, 82711, 84639, 86995, 95839, 96472, 98059, 98651, 100951, 103000, 105419, 105671, 107271, 108824, 112144, 117107, 119755, 123163, 126355, 128547

Offset

1,1

Links

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

Mathematica

cf45Q[n_]:=Module[{c=Sqrt[n]}, !IntegerQ[c]&&Count[ContinuedFraction[ c] [[2]], 1]==45]; Select[Range[150000], cf45Q] (* Harvey P. Dale, Dec 24 2012 *)

Crossrefs

Sequence in context: A207794 A368426 A256840 * A043654 A188104 A278903

Adjacent sequences: A031810 A031811 A031812 * A031814 A031815 A031816

Keyword

nonn

Author

David W. Wilson

Status

approved