A031594 that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 96.

9218, 9234, 9278, 9286, 9302, 9314, 9318, 9326, 9346, 9358, 9382, 9406, 9426, 9446, 9462, 9474, 9502, 9518, 9538, 9558, 9566, 9574, 9598, 9602, 20739, 20811, 20814, 20841, 20847, 20877, 20892, 20901, 20913, 20919, 20937, 20949, 20964, 20973, 20991

Offset

1,1

Links

Table of n, a(n) for n=1..39.

Mathematica

cf96Q[n_]:=Module[{s=Sqrt[n], cf, len}, cf=If[IntegerQ[s], {1}, ContinuedFraction[ s][[2]]]; len=Length[cf]; EvenQ[len]&&cf[[len/2]] == 96]; Select[Range[21000], cf96Q] (* Harvey P. Dale, May 15 2018 *)

Crossrefs

Sequence in context: A204103 A209595 A223303 * A262508 A272596 A189984

Adjacent sequences: A031591 A031592 A031593 * A031595 A031596 A031597

Keyword

nonn

Author

David W. Wilson

Status

approved