Hi I'm using wxmaxima to evaluate

U(y,z):=(p*c^2)/(2*mu)*(1-(2/c)^2+4*sum((-1)^k/(alpha*k^3)*(cosh((alpha*y)/c)/cosh((alpha*b)/c)*cosh((alpha*z)/c)),k,1,inf))

alpha = (2*k-1)*(pi/2)

at y = 0.08333335

and z = 0.00001

the program won't evaluate the sum all it will do is give the equation back with the summation sign.

I want the answer for U(0.08333335, 0.00001).

Any help would be appreciated