dnbinom(x, size, prob, mu, log = FALSE) #P(X = x)
pnbinom(q, size, prob, mu, lower.tail = TRUE, log.p = FALSE) #P(X <= x)
qnbinom(p, size, prob, mu, lower.tail = TRUE, log.p = FALSE) #returns x where P(X <= x)=p
rnbinom(n, size, prob, mu) #Generate a sample of n elements