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A031867
Period of continued fraction for sqrt(n) contains exactly 99 ones.
1
48379, 56191, 69451, 75007, 107875, 118567, 137059, 145336, 157399, 190819, 194111, 230591, 230839, 248023, 253991, 261551, 287459, 318667, 325816, 343759, 368019, 370239, 391911, 392491, 409907, 424591, 442216, 446395, 448743, 460816
OFFSET
1,1
MATHEMATICA
cf99Q[n_]:=With[{s=Sqrt[n]}, If[IntegerQ[s], 1, Count[ContinuedFraction[s][[2]], 1]]==99]; Select[ Range[461000], cf99Q] (* Harvey P. Dale, Jun 20 2024 *)
CROSSREFS
Sequence in context: A253501 A253455 A233890 * A151839 A151876 A083627
KEYWORD
nonn
STATUS
approved