This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
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NotElement ()

NotElement[x, dom]
or xdom asserts that x is not an element of the domain dom.
NotElement[x1|...|xn, dom]
asserts that none of the x_i are elements of dom.
NotElement[patt, dom]
asserts that any expression matching the pattern patt is not an element of the domain dom.
  • xdom can be entered as x Esc !el Esc dom or x\[NotElement]dom.
New in 6