OFFSET
0,1
LINKS
Eric Weisstein's MathWorld, Multivariate Zeta Function
Wikipedia, Multiple zeta function
FORMULA
zetamult(2,4) = Sum_{m>=2} (Sum_{n=1..m-1} 1/(m^2*n^4)) = (25/12)*zeta(6) - zeta(3)^2.
EXAMPLE
0.67452391403396814049156060825742993927838436513788957970691722144377...
MATHEMATICA
RealDigits[(25/12)*Zeta[6] - Zeta[3]^2, 10, 103] // First
PROG
(PARI) zetamult([2, 4]) \\ Charles R Greathouse IV, Jan 21 2016
CROSSREFS
KEYWORD
AUTHOR
Jean-François Alcover, Jun 16 2015
STATUS
approved