A020415 Numbers k such that the continued fraction for sqrt(k) has period 76.

1516, 2446, 2551, 4663, 5001, 5014, 5029, 5533, 5756, 6129, 6607, 6881, 6911, 6979, 7099, 7166, 7269, 7886, 8111, 8134, 8189, 8453, 8908, 9134, 9514, 9532, 9767, 10276, 10343, 10449, 10687, 10799, 11572, 11582, 11584, 11852, 11873, 12029, 12295, 12478

Offset

1,1

Links

Table of n, a(n) for n=1..40.

Mathematica

cf76Q[n_]:=Module[{s=Sqrt[n], len}, If[IntegerQ[s], len=1, len= Length[ ContinuedFraction[ s][[2]]]]; len==76]; Select[Range[15000], cf76Q] (* Harvey P. Dale, Apr 16 2013 *)

Crossrefs

Sequence in context: A318713 A252508 A031810 * A257753 A236724 A206654

Adjacent sequences: A020412 A020413 A020414 * A020416 A020417 A020418

Keyword

nonn

Author

David W. Wilson

Status

approved