How can i make a matrix with variable elements?

Hi, i'm trying to make 2*3 matrix as transformation matrix that includes variable elements and use it in a for loop (summing over N',N") as below: ∑_N'N" ((J' S N';Ω'-Σ'-Λ'))*((J" S ";Ω"-Σ"-Λ"))

my question is how to construct such matrices with variable elements? i appreciate if anyone give me a hint.

[dpb]

For what working definition of "variable" in "variable elements", pray tell?