October 8th, 2019
#P (X = 0) lam<-0.3 P<- ppois(0, lam) P
## [1] 0.7408182
#P (X = 1) P<- ppois(1, lam) - ppois(0, lam) P
## [1] 0.2222455
#P (X > 1) P<- ppois(1, lam, lower.tail = FALSE) P
## [1] 0.03693631