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%I #9 Dec 30 2017 17:26:35
%S 1,0,9,1,8,8,2,5,8,8,6,6,4,5,3,0,0,8,5,1,6,5,7,8,2,1,3,0,6,9,9,2,7,3,
%T 8,7,3,3,7,7,5,6,7,8,8,9,5,3,2,4,0,8,6,2,6,3,8,1,2,6,6,6,6,7,4,7,6,6,
%U 6,6,7,7,6,8,4,0,1,2,8,5,8,2,0,4,3,6,9,1,8,0,6,7,4,2,6,5,7,5,7,8
%N Decimal expansion of sum_(n>=1) H(n)^2/n^5 where H(n) is the n-th harmonic number.
%H G. C. Greubel, <a href="/A238168/b238168.txt">Table of n, a(n) for n = 1..10000</a>
%H Philippe Flajolet, Bruno Salvy, <a href="http://algo.inria.fr/flajolet/Publications/FlSa98.pdf">Euler Sums and Contour Integral Representations</a>, Experimental Mathematics 7:1 (1998) page 16.
%F Equals 6*zeta(7) - zeta(2)*zeta(5) - 5/2*zeta(3)*zeta(4).
%e 1.091882588664530085165782130699273873...
%t RealDigits[6*Zeta[7] -Zeta[2]*Zeta[5] -(5/2)*Zeta[3]*Zeta[4],10,100][[1]]
%o (PARI) 6*zeta(7) - zeta(2)*zeta(5) - (5/2)*zeta(3)*zeta(4) \\ _G. C. Greubel_, Dec 30 2017
%Y Cf. A152648, A152649, A152651, A238166, A238167, A238169.
%K nonn,cons
%O 1,3
%A _Jean-François Alcover_, Feb 19 2014