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%I #20 Jun 08 2021 06:25:58
%S 8,7,7,6,4,9,1,4,6,2,3,4,9,5,1,3,0,9,8,1,4,0,8,9,5,7,0,1,8,1,5,7,4,8,
%T 7,4,0,2,3,0,8,4,5,6,5,3,2,7,2,9,7,6,5,6,3,6,6,7,9,2,2,8,6,6,6,0,5,1,
%U 4,5,8,1,1,7,3,4,0,9,7,8,3,7,0,8,1,5,4,0,8,5,6,7,4,6,3,9,8,4,6,4,4,9
%N Decimal expansion of Pi/2 - log(2).
%D Jean-Marie Monier, Analyse, Exercices corrigés, 2ème année MP, Dunod, 1997, Exercice 2.5.2.n, pp. 186 and 223.
%F Equals (-log(4) - psi(1/4) + psi(3/4)) / 2, where psi(x) denotes the digamma function.
%F Equals -Integral_{x=0..1} log(x)/((1+x)*sqrt(1-x^2)) dx. - _Bernard Schott_, Apr 28 2021
%F Equals Sum_{k>=1} (-1)^(k+1)/(k*(2*k-1)). - _Amiram Eldar_, Jun 08 2021
%e 0.87764914623495130981408957018157487402308456532730...
%t RealDigits[N[Pi/2 - Log[2], 105]][[10]]
%o (PARI) Pi/2 - log(2) \\ _Michel Marcus_, Mar 14 2021
%Y Cf. A019669 (Pi/2), A002162 (log(2)).
%K nonn,cons
%O 1,1
%A _Peter Luschny_, Mar 14 2021
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