Large matrix formation and multiplication

I'm trying to work out the best way of creating a large matrix and multiplying it with a scalar. Something like:

| 0| x |20, 10, 10, 10, 10, 10, 10| = |?|

| 0| x |10, 20, 10, 10, 10, 10, 10| = |?|

| 0| x |10, 10, 20, 10, 10, 10, 10| = |?|

|10| x |10, 10, 10, 20, 10, 10, 10| = |?|

| 0| x |10, 10, 10, 10, 20, 10, 10| = |?|

| 0| x |10, 10, 10, 10, 10, 20, 10| = |?|

|10| x |10, 10, 10, 10, 10, 10, 20| = |?|

At the moment I'm considering using nested array lists, but I think it could become complicated and I'm still new to programming. The reason I need the large matrices is for working out forces in a large number of connected objects.

Any suggestions?