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A020415 Numbers k such that the continued fraction for sqrt(k) has period 76. 0
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 7 22:50 EST 2021. Contains 349590 sequences. (Running on oeis4.)