Weierstrass factorization theorem

=The lmentary factors=[1] For $n\in \mathbb {N}$, we define: $E_{o}(z)=1-zE_{n}(z)=(1-z)e^{\sum _{i\in \mathbb {N} }{\frac {z^{i}}{i}}}$

References

• Rudin, W, Real and Complex Analysis, 3rd Ed, Mc Graw Hill, Boston, pp 301 - 304, 1987
• Eric W. Weisstein. "Weierstrass Product Theorem." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/WeierstrassProductTheorem.html