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%I #12 Nov 20 2024 17:41:19
%S 7,6,2,7,5,9,7,6,3,5,0,1,8,1,3,1,8,8,0,6,2,3,2,5,9,8,0,9,6,3,6,1,5,7,
%T 9,3,2,9,2,6,2,9,2,3,7,3,4,8,0,7,2,9,1,5,2,1,7,0,7,1,5,9,8,2,6,4,4,2,
%U 2,6,9,2,9,5,6,2,5,6,1,9,2,1,9,5,4,6,6,1,4,6
%N Decimal expansion of 2/L, where L is the lemniscate constant (A062539).
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Lemniscate_constant">Lemniscate constant</a> (includes this constant).
%H <a href="/index/Ga#gamma_function">Index to sequences related to the Gamma function</a>.
%F Equals 1/A085565.
%F Equals 2*sqrt(2)*Gamma(3/4)^2/Pi^(3/2) = A010466*A175575.
%F Equals Product_{k >= 1} b(k), where b(1) = sqrt(1/2) and, for k >= 2, b(k) = sqrt(1/2 + (1/2)/b(k-1)).
%e 0.76275976350181318806232598096361579329262923734807...
%t First[RealDigits[Sqrt[8]*Gamma[3/4]^2/Pi^(3/2), 10, 100]]
%Y Cf. A010466, A062539, A085565, A175575.
%Y Cf. A377999, A378129, A378130, A378131, A378132.
%K nonn,cons,easy
%O 0,1
%A _Paolo Xausa_, Nov 17 2024