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A020350
Numbers k such that the continued fraction for sqrt(k) has period 11.
0
61, 97, 233, 298, 317, 554, 757, 773, 794, 797, 1322, 1385, 1429, 1625, 1658, 1730, 1769, 1865, 1973, 2069, 2081, 2218, 2249, 2285, 2357, 2465, 2690, 2890, 2941, 2986, 3233, 3242, 3341, 3538, 3545, 3986, 4250, 4274, 4553, 4597, 4610, 4649, 4682, 4889
OFFSET
1,1
MATHEMATICA
cf11Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Length[ ContinuedFraction[ s][[2]]]]==11]; Select[Range[5000], cf11Q] (* Harvey P. Dale, Mar 28 2019 *)
CROSSREFS
Sequence in context: A045562 A104229 A088787 * A142108 A033239 A106390
KEYWORD
nonn
STATUS
approved