There are several notational conventions for representing repeating decimals. Beams are also used as a notational abbreviation to indicate tremolos and reiterations. Euler introduced and popularized several notational conventions through his numerous and widely circulated textbooks. Two competing notational conventions split the field of matrix calculus into two separate groups. This is simply a notational convention to avoid parentheses. First, the equation is parsed into a tree structure to avoid notational idiosyncrasies. An operation that is mathematically associative, by definition requires no notational associativity. Notational conventions&colon; Let be a variable ranging over sets of sentences. The notational conventions for sequences normally apply to nets as well. We adopt the same notational conventions as above. By notational convention the recitatives are in common time. The notational conventions used in this article are as follows. The same notational conventions mentioned above for centralizers also apply to normalizers. See matrix multiplication for the notational correspondence between matrices and the dot and tensor products. Functions of the form "pp(u,m)" are trivially set to unity for notational completeness.