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Decimal expansion of 2*sin(Pi/96).
2

%I #13 Jun 26 2023 02:21:31

%S 6,5,4,3,8,1,6,5,6,4,3,5,5,2,2,8,4,1,2,7,3,1,9,8,5,2,6,3,4,5,7,6,2,5,

%T 2,2,2,9,9,2,5,2,5,4,5,0,3,3,9,2,3,9,3,7,5,6,1,9,1,7,6,7,5,1,4,6,3,7,

%U 4,7,0,4,2,6,5,3,4,7,8,5,4,5,9,6,0,4,9,6,7,0,8,9,7,2,8,3,3,7,9,8,4,9

%N Decimal expansion of 2*sin(Pi/96).

%C This constant appears in a historic problem posed by Adriaan van Roomen (Adrianus Romanus) in his Ideae mathematicae from 1593, solved by Viète. See the Havil reference, problem 1 (with a correction), pp. 69-74.

%C For details see the comments under A302711, also for the original reference.

%D Julian Havil, The Irrationals, A Story of the Numbers You Can't Count On, Princeton University Press, Princeton and Oxford, 2012, pp. 69-74.

%F The constant is 2*sin(Pi/96) = sqrt(2 - sqrt(2 + sqrt(2 + sqrt(2 + sqrt(3))))).

%e 2*sin(Pi/96) = 0.0654381656435522841273198526345762522299252545033923937561...

%t RealDigits[2*Sin[Pi/96], 10, 120][[1]] (* _Amiram Eldar_, Jun 26 2023 *)

%Y Cf. A302711.

%K nonn,cons,easy

%O -1,1

%A _Wolfdieter Lang_, Apr 28 2018