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Decimal expansion of sum_(n>=1) H(n)^2/n^7 where H(n) is the n-th harmonic number (Quadratic Euler Sum S(2,7)).
3

%I #6 Feb 19 2014 11:25:27

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

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

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

%N Decimal expansion of sum_(n>=1) H(n)^2/n^7 where H(n) is the n-th harmonic number (Quadratic Euler Sum S(2,7)).

%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 24.

%F zeta(3)^3/3-5/2*zeta(4)*zeta(5)-7/2*zeta(3)*zeta(6)-zeta(2)*zeta(7)+55/6*zeta(9).

%e 1.019483497494382286206496675928126515...

%t Zeta[3]^3/3 - 5/2*Zeta[4]*Zeta[5] - 7/2*Zeta[3]*Zeta[6] - Zeta[2]*Zeta[7] + 55/6*Zeta[9] // RealDigits[#, 10, 100]& // First

%Y Cf. A152648, A152649, A152651, A218505, A238168, A238181, A238182.

%K nonn,cons

%O 1,4

%A _Jean-François Alcover_, Feb 19 2014