= Jensen's formula
{c}
{title2=$\log|f(0)|+\sum_{|a_j|<R}\log(R/|a_j|)=\tfrac1{2\pi}\int_0^{2\pi}\log|f(Re^{i\theta})|\,d\theta$}
{wiki}
For a <holomorphic function> nonzero at zero and without boundary zeros, the formula relates its interior zeros, counted by multiplicity, to the circle mean of its logarithmic modulus. Divide out the finite interior zero factors; the remaining logarithmic modulus is <harmonic>, and each zero contributes $\log(R/|a_j|)$ by the <harmonic> mean-value formula. Boundary radii follow by limits where appropriate.
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