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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E23">Th22</font></span>: <a NAME="T22"><span class="comment"><font color="firebrick">:: NAT_6:22</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">p</font> being   <a href="xxreal_0.html#V2" title="XXREAL_0:attr.2">positive</a>  <a href="ordinal1.html#NM6" title="ORDINAL1:NM.6">Nat</a><br/>  for <font color="Olive" title="b2">a</font> being   <a href="int_1.html#NM1" title="INT_1:NM.1">Integer</a> holds <br/> ( <font color="Olive" title="b2">a</font> <a href="int_5.html#R1" title="INT_5:pred.1">is_quadratic_residue_mod</a> <font color="Olive" title="b1">p</font> iff  ex <font color="Olive" title="b3">x</font> being   <a href="int_1.html#NM1" title="INT_1:NM.1">Integer</a> st <font color="Olive" title="b3">x</font> <a href="newton.html#K1" title="NEWTON:func.1">|^</a> 2,<font color="Olive" title="b2">a</font> <a href="int_1.html#R2" title="INT_1:pred.2">are_congruent_mod</a> <font color="Olive" title="b1">p</font> )</div></div>
