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%I #19 Oct 01 2022 00:20:34
%S 4,8,1,5,7,4,6,1,8,8,0,7,5,2,8,6,4,4,3,3,2,1,6,2,3,5,3,0,5,6,9,7,0,5,
%T 7,5,2,1,9,0,7,8,8,9,1,7,5,2,2,9,9,9,3,5,5,5,4,2,0,5,3,7,2,9,7,9,2,9,
%U 8,1,0,3,3,0,5,4,6,2,1,3,9,0,4,3,0,7,9,1,4,1,0,8,9,4,2,0,3,1,8,3,1,3,9,8,1,7,3,8,3,0
%N Decimal expansion of tan(Pi/7).
%C Root of the equation -7 + 35*x^2 - 21*x^4 + x^6 = 0. - _Vaclav Kotesovec_, Apr 04 2021
%H G. C. Greubel, <a href="/A343058/b343058.txt">Table of n, a(n) for n = 0..10000</a>
%e 0.48157461880752864433216235305697...
%t RealDigits[Tan[Pi/7], 10, 120][[1]] (* _Amiram Eldar_, Apr 27 2021 *)
%o (PARI) tan(Pi/7)
%o (SageMath) numerical_approx(tan(pi/7), digits=123) # _G. C. Greubel_, Sep 30 2022
%Y Cf. A323601 (sin(Pi/7)), A073052 (cos(Pi/7)).
%K nonn,cons,easy
%O 0,1
%A _Seiichi Manyama_, Apr 04 2021