A197110 Decimal expansion of Pi^4/120.

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

Offset

0,1

Comments

Decimal expansion of the double zeta function zeta(2,2). Not to be confused with the Hurwitz zeta function of two arguments or with the second derivative of the Riemann zeta function.

Links

Table of n, a(n) for n=0..86.

R. E. Crandall and J. P. Buhler, On the evaluation of Euler sums, Exper. Math. 3 (1994), 275.

Wikipedia, Multiple zeta function

Index entries for transcendental numbers

Formula

Equals Sum_{n >=2} Sum_{m=1..n-1} 1/(n*m)^2.

Example

0.8117424... = A164109/40 .

Maple

evalf(Pi^4/120) ;

Mathematica

First[RealDigits[Pi^4/120, 10, 100]] (* Geoffrey Critzer, Nov 03 2013 *)

Prog

(PARI) Pi^4/120 \\ Charles R Greathouse IV, Apr 17 2015
(PARI) zetamult([2, 2]) \\ Charles R Greathouse IV, Apr 17 2015

Crossrefs

Cf. A092425, A164109.

Sequence in context: A172428 A248581 A178163 * A109571 A366494 A133823

Adjacent sequences: A197107 A197108 A197109 * A197111 A197112 A197113

Keyword

cons,nonn,easy

Author

R. J. Mathar, Oct 10 2011

Extensions

More terms from D. S. McNeil, Oct 10 2011

Definition simplified by R. J. Mathar, Feb 05 2013

Status

approved