DocumentationMathematicaThe Mathematica BookMathematica Reference GuideSome General Notations and Conventions
Iterators are used in such functions as Sum, Table, Do and Range.
The iteration parameters imin, imax and di do not need to be integers. The variable i is given a sequence of values starting at imin, and increasing in steps of di, stopping when the next value of i would be greater than imax. The iteration parameters can be arbitrary symbolic expressions, so long as (imax-imin)/di is a number.
When several iteration variables are used, the limits for the later ones can depend on the values of earlier ones.
The variable i can be any symbolic expression; it need not be a single symbol. The value of i is automatically set up to be local to the iteration function. This is effectively done by wrapping a Block construct containing i around the iteration function.
The procedure for evaluating iteration functions is described in Section A.4.2.