CAS programs, order of LOCAL variables?

[parisse]

If you declare local variables and assign them, then priorities for assignation apply, and local a:=1,j is like local a:=(1,j). You must add parenthesis: local (a:=1),j; or enter 2 local statements or assign them after declaration.
For sums, there is no table lookup. The current version of Xcas returns ln(2) for sum( ((-1)^(j+1))/j,j,1,inf), therefore it should work in a future release on the Prime.