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Expansion of golden ratio (1 + sqrt(5))/2 in base 2.
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%I #21 Feb 06 2023 12:48:10

%S 1,1,0,0,1,1,1,1,0,0,0,1,1,0,1,1,1,0,1,1,1,1,0,0,1,1,0,1,1,1,0,0,1,0,

%T 1,1,1,1,1,1,1,0,1,0,0,1,0,1,0,0,1,1,1,1,1,0,0,0,0,0,1,0,1,0,1,1,1,1,

%U 1,0,0,1,1,1,0,0,1,1,1,0,0,1,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,0,1,1,1,0,0

%N Expansion of golden ratio (1 + sqrt(5))/2 in base 2.

%C Differs from A004555 in the 2nd digit. - _R. J. Mathar_, Dec 15 2008

%e 1.1001111000110111011110011011100101...

%t RealDigits[ (1+Sqrt[5])/2, 2, 1000][[1]]

%o (PARI) concat(binary((1+sqrt(5))/2)) \\ _Michel Marcus_, Dec 14 2017

%o (PARI) a(n) = floor(quadgen(5)*2^(n-1))%2 \\ _Chittaranjan Pardeshi_, Feb 06 2023

%Y Cf. A001622, A004555, A004714, A169868.

%K base,cons,easy,nonn

%O 1,1

%A _Benoit Cloitre_, Mar 09 2002