The multiplicative group $GF(p^n)^* := GF(p^n) - {0}$ is shown to be cyclic. If we consider $GF(p^n)$ as a extension of $GF(p)$, does a primitive element $a$ in $GF(p^n)$ necessarily generate $GF(p^n)^*$?
@Simple Do you know that for a function to be a probability mass function then the sum of the function over all the all the possible values the random variable can attain is 1?
@Simple An indicator function is 0 when the condition (in this case $Y>0$) is false and 1 when the condition is true. You are right in that you are summing the Poisson, but there's an easier way to calculate it without having to do any sums