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Decimal expansion of Product_{k>=1} Gamma(2k/(2k-1)) / Gamma(1+1/(2k)).
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%I #18 Jun 11 2024 12:47:05

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

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

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

%N Decimal expansion of Product_{k>=1} Gamma(2k/(2k-1)) / Gamma(1+1/(2k)).

%H Henri Cohen, Fernando Rodriguez Villegas, and Don Zagier, <a href="https://dx.doi.org/10.1080/10586458.2000.10504632">Convergence Acceleration of Alternating Series</a>, Exp. Math. 9 (1) (2000) 3-12.

%H Vaclav Kotesovec, <a href="https://mathematica.stackexchange.com/questions/304035/why-do-i-get-different-results-for-the-products-of-two-identical-expressions">Why do I get different results for the products of two identical expressions ?</a>, Mathematica Stack Exchange, Jun 10 2024.

%e 1.06215090557105728069683736293...

%p evalf(Product(2*k*GAMMA(1/(2*k - 1))/((2*k - 1)*GAMMA(1/(2*k))), k = 1..infinity), 120); # _Vaclav Kotesovec_, Jun 10 2024

%o (PARI) default(realprecision, 200); exp(sumpos(k=1, log(2*k) + log(gamma(1/(2*k-1))) - log(2*k-1) - log(gamma(1/(2*k))) )) \\ _Vaclav Kotesovec_, Jun 10 2024

%Y Cf. A303670.

%K cons,nonn

%O 1,3

%A _R. J. Mathar_, Jun 15 2023

%E More terms from _Vaclav Kotesovec_, Jun 10 2024