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%I #8 Sep 01 2014 09:05:09
%S 1,8,9,4,0,0,6,6,5,3,5,4,7,6,8,0,5,9,0,9,4,2,4,3,8,0,7,8,8,8,2,0,5,6,
%T 3,7,8,1,9,0,4,9,6,4,5,8,8,3,9,4,2,7,3,9,2,2,1,6,6,4,2,2,4,1,9,3,4,5,
%U 2,8,7,0,8,7,1,5,9,9,8,7,0,4,4,8,1,9,9,1,1,9,9,9,9,8,6,0,3,0,2,2,8,9,4,7,8,0,6,6,4,1,8,6,7,6,6,7,1,8,6,4,5,1,1,1,2,9,3,7,6,2
%N Decimal expansion of length/width of a meta-1st electrum rectangle.
%C See A188618 for the definition of 1st electrum rectangle. Briefly, it is a rectangle such that the removal of a golden rectangle from one end leaves a silver rectangle.
%H Clark Kimberling, <a href="http://www.jstor.org/stable/27963362">A Visual Euclidean Algorithm</a>, The Mathematics Teacher 76 (1983) 108-109.
%t t=(1+3^(1/2))/2; r=(t+(t^2+4)^(1/2))/2
%t FullSimplify[r]
%t N[r, 130]
%t RealDigits[N[r, 130]][[1]]
%Y Cf. A188618, A188619, A188639.
%K nonn,cons
%O 1,2
%A _Clark Kimberling_, Apr 06 2011
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