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%I #18 Aug 28 2021 10:08:19
%S 46,76,103,127,184,213,236,239,247,263,276,295,304,329,351,355,364,
%T 366,369,386,426,428,429,460,479,512,535,558,605,609,636,640,688,708,
%U 717,734,748,767,775,802,815,820,824,832,851,864,887,995,1027,1068,1071,1077
%N Numbers k such that the continued fraction for sqrt(k) has period 12.
%H Robert P. P. McKone, <a href="/A020351/b020351.txt">Table of n, a(n) for n = 1..9999</a>
%t Select[Range[1077],Length[Last[ContinuedFraction[Sqrt[#]]]] == 12 &] (* _Robert P. P. McKone_, Aug 27 2021, after _Alonso del Arte_ *)
%Y Contains A237611.
%K nonn
%O 1,1
%A _David W. Wilson_