A244664 Decimal expansion of sum_(n>=1) (H(n,2)/n^2) where H(n,2) = A007406(n)/A007407(n) is the n-th harmonic number of order 2.

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

Offset

1,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Philippe Flajolet, Bruno Salvy, Euler Sums and Contour Integral Representations, Experimental Mathematics 7:1 (1998) page 23.

Formula

7*Pi^4/360 = (7/4)*A013662.

Example

1.894065658994491835153006468947043829855814165857772088445208377027211...

Mathematica

RealDigits[7/4*Zeta[4], 10, 100] // First

Prog

(PARI) 7*zeta(4)/4 \\ Michel Marcus, Jul 04 2014

Crossrefs

Cf. A007406, A007407, A013662.

Sequence in context: A360148 A021532 A188638 * A010532 A317864 A335963

Adjacent sequences: A244661 A244662 A244663 * A244665 A244666 A244667

Keyword

nonn,cons

Author

Jean-François Alcover, Jul 04 2014

Status

approved