The implication <math>x \Rightarrow y</math> is written <math>(x (y)),\!</math> which can be read "not <math>x\!</math> without <math>y\!</math>" if that helps to remember the meaning.
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The implication <math>x \Rightarrow y</math> is written <math>(x (y)).\!</math> Reading the latter as "not <math>x\!</math> without <math>y\!</math>" helps to recall its implicational sense.