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Decimal expansion of product_{p=primes} (1-1/(2^p+1)).
3

%I #7 Jul 23 2024 15:43:26

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

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

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

%N Decimal expansion of product_{p=primes} (1-1/(2^p+1)).

%C Inverse of the constant A184083.

%F Equals product_{p in A000040} (1-1/(2^p+1)) = 1/ product_p (1+2^(-p)) = product_{n>=1} (1-1/A098640(n)).

%e (1-1/5) *(1-1/9) *(1-1/33) * (1-1/129) *(1-1/2049)* ... = 0.6837928423594743689943636...

%t RealDigits[Times@@Table[1-1/(2^p+1),{p,Prime[Range[1000]]}],10,100][[1]] (* _Harvey P. Dale_, Jul 23 2024 *)

%K cons,nonn

%O 0,1

%A _R. J. Mathar_, Jan 09 2011