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Decimal expansion of Sum_{k>=0} 1/Product_{i=0..k} (2^(2^i) - 1).
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%I #14 Feb 19 2024 02:08:13

%S 1,3,5,5,6,4,2,7,0,2,8,5,4,8,1,6,7,2,3,3,3,3,2,6,2,7,1,4,5,9,0,7,3,9,

%T 5,5,2,3,3,9,8,8,2,9,3,8,5,9,9,4,8,7,7,2,8,4,6,8,9,7,8,5,8,5,3,3,9,7,

%U 5,0,9,4,9,9,7,7,7,2,1,4

%N Decimal expansion of Sum_{k>=0} 1/Product_{i=0..k} (2^(2^i) - 1).

%F From _Amiram Eldar_, Feb 19 2024: (Start)

%F Equals Sum_{n>=0} 1/A370458(n).

%F Equals 1/A215016 - 3/2. (End)

%e 1.3556427028548167233332627145907395523398829385994877...

%t RealDigits[1/NProduct[1 - 1/2^(2^k), {k, 0, Infinity}, WorkingPrecision -> 120] - 3/2][[1]] (* _Amiram Eldar_, Feb 19 2024 *)

%o (PARI) 1/prodinf(k = 0, 1 - 1/2^(2^k)) - 3/2 \\ _Amiram Eldar_, Feb 19 2024

%Y Cf. A215016, A258715, A258716, A370458.

%K nonn,cons

%O 1,2

%A _N. J. A. Sloane_, Jun 15 2015