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A031683 Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 95. 0

%I #14 Aug 18 2021 00:10:32

%S 56669,110938,183265,184981,274697,508594,512881,653153,656389,659633,

%T 664514,824825,828461,1195178,1203938,1214933,1217138,1411969,1419106,

%U 1421489,1426261,1433434,1435829,1438226,1659673,1669993,1899725

%N Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 95.

%t cf95Q[n_]:=Module[{s=Sqrt[n],cf,len},cf=If[IntegerQ[s],{1,1}, ContinuedFraction[ s][[2]]];len=Length[cf];OddQ[len]&&cf[[(len+1)/2]] == 95]; Select[Range[2*10^6],cf95Q] (* _Harvey P. Dale_, Aug 11 2015 *)

%K nonn

%O 1,1

%A _David W. Wilson_

%E Corrected and definition clarified by _Harvey P. Dale_, Aug 11 2015

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Last modified April 19 09:23 EDT 2024. Contains 371782 sequences. (Running on oeis4.)