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A247621 Decimal expansion of Sum_{k>=1} 1/(2*k)-tanh(1/(2*k)). 1


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

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

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

%N Decimal expansion of Sum_{k>=1} 1/(2*k)-tanh(1/(2*k)).

%H Philippe Flajolet, √Čric Fusy, Xavier Gourdon, Daniel Panario and Nicolas Pouyanne, <a href="http://arxiv.org/abs/math/0606370">A Hybrid of Darboux's Method and Singularity Analysis in Combinatorial Asymptotics</a>, arXiv:math.CO/0606370, p. 18

%e 0.04615145130591420884656838354174674728274955974710537814789097038...

%p evalf(sum(1/(2*k)-tanh(1/(2*k)), k=1..infinity), 120)

%o (PARI) default(realprecision,150); sumpos(k=1,(1/(2*k)-tanh(1/(2*k))))

%Y Cf. A003483.

%K nonn,cons

%O 0,2

%A _Vaclav Kotesovec_, Sep 21 2014

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Last modified April 22 22:19 EDT 2021. Contains 343197 sequences. (Running on oeis4.)