Where can I find some nice formulas for the lambda invariant of an elliptic curve? I vaguely recall there's a nice product formula in terms of $q$, but a Google search didn't give me much. Also, are there other formulas that express the $\lambda$ function in terms of $q$ or give a precise formula for the coefficients of its $q$-expansion?
At the moment I have two books at my disposal: Silverman's Advanced Topics in the Arithmetic of Elliptic Curves, and Diamond and Shurman. Silverman gives nice formulas for the $j$-invariant, but I can't find much on the $\lambda$-invariant, unfortunately.