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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E20">Th21</font></span>: <a NAME="T19"><span class="comment"><font color="firebrick">:: MESFUN15:19</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">X</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a> <br/>  for <font color="Olive" title="b2">S</font> being   <a href="prob_1.html#NM3" title="PROB_1:NM.3">SigmaField</a> of <font color="Olive" title="b1">X</font><br/>  for <font color="Olive" title="b3">E</font> being   <a href="nat_1.html#NM1" title="NAT_1:NM.1">sequence</a> of <font color="Olive" title="b2">S</font><br/>  for <font color="Olive" title="b4">f</font> being   <a href="partfun1.html#NM1" title="PARTFUN1:NM.1">PartFunc</a> of <font color="Olive" title="b1">X</font>,<a href="numbers.html#K6" title="NUMBERS:func.6">ExtREAL</a>  st (  for <font color="Olive" title="b5">n</font> being   <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a> holds  <font color="Olive" title="b4">f</font> is <font color="Olive" title="b3">E</font> <a href="nat_1.html#K8" title="NAT_1:func.8">.</a> <font color="Olive" title="b5">n</font> <a href="mesfunc1.html#V1" title="MESFUNC1:attr.1">-measurable</a>  ) holds <br/><font color="Olive" title="b4">f</font> is  <a href="measur11.html#K3" title="MEASUR11:func.3">Union</a> <font color="Olive" title="b3">E</font> <a href="mesfunc1.html#V1" title="MESFUNC1:attr.1">-measurable</a> </div></div>
