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A020363
Numbers k such that the continued fraction for sqrt(k) has period 24.
0
271, 382, 581, 607, 681, 753, 789, 826, 871, 911, 1017, 1072, 1103, 1147, 1233, 1255, 1262, 1349, 1359, 1438, 1614, 1674, 1711, 1795, 1836, 1838, 1868, 1888, 1908, 1922, 1982, 2048, 2051, 2063, 2078, 2107, 2119, 2143, 2154, 2254, 2364, 2367, 2414, 2439
OFFSET
1,1
MATHEMATICA
cf24Q[n_]:=Module[{s=Sqrt[n], c}, c=If[IntegerQ[s], {1, 1}, ContinuedFraction[ s]][[2]]; Length[c]==24]; Select[Range[2500], cf24Q] (* Harvey P. Dale, Mar 20 2021 *)
CROSSREFS
Sequence in context: A174402 A048295 A257210 * A051965 A142762 A141029
KEYWORD
nonn
STATUS
approved