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A031837
Period of continued fraction for sqrt(n) contains exactly 69 ones.
0
25519, 47167, 51067, 75839, 103027, 123463, 123971, 126655, 128083, 132823, 145847, 151411, 154507, 159895, 160043, 187384, 198067, 202211, 216875, 217807, 218951, 219055, 219271, 223687, 234779, 234955, 236099, 242215, 246999, 247487
OFFSET
1,1
MATHEMATICA
cf69Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 1, Count[ContinuedFraction[s][[2]], 1]]==69]; Select[ Range[250000], cf69Q] (* Harvey P. Dale, Apr 01 2023 *)
CROSSREFS
Sequence in context: A324635 A242141 A124997 * A237865 A202646 A210093
KEYWORD
nonn
STATUS
approved