Here are two ways of looking at the divisibility relation, a dyadic relation of fundamental importance in number theory.
Table 1 shows the first few ordered pairs of the relation on positive integers that corresponds to the relative term, “divisor of”. Thus, the ordered pair appears in the relation if and only if
divides
for which the usual notation is
Table 2 shows the same information in the form of a logical matrix. This has a coefficient of in row
and column
when
otherwise it has a coefficient of
(The zero entries have been omitted here for ease of reading.)
Just as matrices in linear algebra represent linear transformations, these logical arrays and matrices represent logical transformations.
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