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%I #12 Nov 21 2024 07:52:38
%S 2,2,3,7,0,3,5,7,5,9,2,8,7,4,1,1,8,7,4,3,3,5,3,2,6,5,8,7,6,1,7,5,4,4,
%T 1,6,2,7,6,6,0,7,4,8,3,8,4,1,3,5,0,0,7,5,3,3,1,8,9,4,6,1,3,8,9,5,7,8,
%U 8,7,1,9,2,5,2,2,1,6,3,7,8,1,0,2,1,9,2,4,2,4,3,8,4,0,6,3,9,6,6,9
%N Decimal expansion of arccos(-1/r), where r = (1+sqrt(5))/2 (the golden ratio).
%C Let c1 and c2 be the constants at A195692 and A195694; then c1+c2 = Pi.
%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%e arccos(-1/r) = 2.2370357592874118743353265876175441...
%t (See A195692.)
%t RealDigits[ArcCos[-1/GoldenRatio],10,120][[1]] (* _Harvey P. Dale_, Jan 15 2012 *)
%o (PARI) acos(-2/(sqrt(5)+1)) \\ _Charles R Greathouse IV_, Nov 21 2024
%Y Cf. A001622, A175288, A195692, A195693.
%K nonn,cons
%O 1,1
%A _Clark Kimberling_, Sep 22 2011