|   | 1 |  initial version  | 
How about something like:
\begin{sagesilent}
tension (lambda_z, s_k) = lambda_z * s_k
lambda_za = 5
s_ka = 4
\end{sagesilent}
$ \sage {tension} = \sage{tension (lambda_za, s_ka)}$
\end{document}
You won't get the 5*4 output, but you'll get the definition of the function, at least.
 Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.
 
                
                Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.