Syntax::tsntxi: 
                                     i θ       i θ
                                         ℓ        j
   "W  -        ∑         ln | e        - e      |"
           1 ≤ ℓ < j ≤ n
     is incomplete; more input is needed.

ToExpression::esntx: 
   Could not parse W=-\sum_{1\leq\ell
<j\leq
     n}\ln|e^{i\theta_{\ell}}-e^{i\theta_{j}}| as input.

  <math 
    xmlns='http://www.w3.org/1998/Math/MathML'>
    <semantics>
      <mi>$Failed</mi>
      <annotation-xml encoding='MathML-Content'>
        <ci>$Failed</ci>
      </annotation-xml>
    </semantics>
  </math>