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%I #10 Jan 01 2024 14:15:16
%S 1,5,2,6,7,5,3,3,5,3,3,5,8,7,4,1,2,0,5,2,0,5,6,7,1,9,9,1,9,1,0,9,8,0,
%T 1,4,5,7,7,4,3,5,9,2,1,0,9,6,7,5,0,7,0,2,1,5,8,1,1,6,2,4,1,9,0,7,5,9,
%U 7,9,0,6,4,3,5,5,2,7,9,0,3,4,7,9,0,2,8,1,5,0,4,6,5,7,6,9,1,2,2,7,1,9,9,0,8
%N Decimal expansion of 4 * Product_{i=1..inf} (1-3/(2*(i+1)))^(1/2^i).
%D D.-Z. Du and F. K. Hwang, Combinatorial Group Testing and Its Applications, World Scientific, 2nd ed., 2000; p. 37.
%e 1.52675335335...
%t digits = 105; 4*NProduct[ (1-3/(2*(i+1)))^(1/2^i), {i, 1, Infinity}, WorkingPrecision -> digits+5, NProductFactors -> 4*digits] // RealDigits[#, 10, digits]& // First (* _Jean-François Alcover_, Mar 07 2013 *)
%Y 4*A054399.
%K nonn,easy,cons
%O 1,2
%A _N. J. A. Sloane_, May 22 2000
%E More terms from _David Wasserman_, Mar 04 2002