but exp(something) = 0 ? thats not possible ln(0), plus in poisson P(X=0) is the highest value

perhaps with the cumulative P(x=1)=0.4 P(x=2)=0.67 with d=2 but i didnt find the answer to that neither

if that 1 or 2 happen conditionally after 100 tries, so in 100 you will have 1 or 2 (if the event happens) or 0 (99% of time), perhaps that could be a poisson aprox