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%I #11 Jun 14 2013 11:01:11
%S 1,6,4,2,1,8,8,4,3,5,2,2,2,1,2,1,1,3,6,8,7,3,6,2,7,9,8,8,9,2,2,9,4,0,
%T 3,4,4,1,8,3,8,2,3,4,5,5,4,8,4,8,8,7,4,3,0,0,7,7,6,2,0,4,2,0,7,7,0,4,
%U 6,6,5,6,9,5,5,2,5,0,2,4,9,2,8,4,5,6,4,0,8,3,3,2,7,7,0,0,7,9,7,1
%N Decimal expansion of the 2nd Lebesgue constant L2.
%D Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, page 251.
%H Eric Weisstein's MathWorld, <a href="http://mathworld.wolfram.com/LebesgueConstants.html">Lebesgue constants</a>
%F (1/Pi)*integral_{t=0..Pi} abs(sin(5*t/2))/sin(t/2)
%F Equals 1/5 + sqrt(25 - 2*sqrt(5))/Pi.
%e 1.6421884352221211368736279889229403441838234554848874300776204207704665695525...
%t RealDigits[1/5 + Sqrt[25 - 2*Sqrt[5]]/Pi, 10, 100][[1]]
%Y Cf. A226654 (L1), A226656 (L3).
%K cons,nonn
%O 1,2
%A _Jean-François Alcover_, Jun 14 2013