not (forall s in S)
<math xmlns="http://www.w3.org/1998/Math/MathML">
<apply>
<not/>
<apply>
<forall/>
<bvar>
<ci>s</ci>
</bvar>
<apply>
<in/>
<ci>s</ci>
<ci>S</ci>
</apply>
</apply>
</apply>
</math>
Author: Design Science, Inc. (E. Cannon, E. Tabacman, R.Miner)