%I #12 Aug 17 2021 23:48:27
%S 198,206,214,238,242,246,254,444,453,471,489,501,507,516,537,543,573,
%T 788,796,844,860,876,892,908,916,924,932,940,956,964,972,988,1004,
%U 1020,1230,1245,1255,1270,1345,1355,1405,1420,1470,1505,1545,1555,1595,1770,1866
%N that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 14.
%H Harvey P. Dale, <a href="/A031512/b031512.txt">Table of n, a(n) for n = 1..1000</a>
%t cf14Q[n_]:=Module[{s=Sqrt[n],cf,len},cf=If[IntegerQ[s],{1},ContinuedFraction[s][[2]]];len=Length[cf];EvenQ[len]&&cf[[len/2]]==14]; Select[Range[2000],cf14Q] (* _Harvey P. Dale_, Apr 04 2013 *)
%K nonn
%O 1,1
%A _David W. Wilson_
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