Generating function
Poisson generating function

The Poisson generating function of a sequence a is PG (a n; x) = ∑ n = 0 ∞ a n e − x x n n ! = e − x EG (a n; x). {\displaystyle \operatorname {PG} (a_{n};x)=\sum _{n=0}^{\infty }a_{n}e^{-x}{\frac {x^{n}}{n!}}=e^{-x}\,\operatorname {EG} (a_{n};x).}
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