%I #11 Dec 07 2016 10:32:28
%S 8,5,84,2400,1691,11480,118455,352692,1401961,1663145124,1802526192,
%T 15798984680,297278169720,1479041362764,1551248530483,42254295673488,
%U 1445285680561323,28154300465964144,49087267967218280,373205366478956820
%N Denominators a(n) of Pythagorean approximations b(n)/a(n) to sqrt(5).
%C See A195500 for a discussion and references.
%t r = Sqrt[5]; z = 24;
%t p[{f_, n_}] := (#1[[2]]/#1[[
%t 1]] &)[({2 #1[[1]] #1[[2]], #1[[1]]^2 - #1[[
%t 2]]^2} &)[({Numerator[#1], Denominator[#1]} &)[
%t Array[FromContinuedFraction[
%t ContinuedFraction[(#1 + Sqrt[1 + #1^2] &)[f], #1]] &, {n}]]]];
%t {a, b} = ({Denominator[#1], Numerator[#1]} &)[
%t p[{r, z}]] (* A195532, A195533 *)
%t Sqrt[a^2 + b^2] (* A195534 *)
%t (* by _Peter J. C. Moses_, Sep 02 2011 *)
%Y Cf. A195500, A195533, A195534.
%K nonn,frac
%O 1,1
%A _Clark Kimberling_, Sep 20 2011
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