Is there bin aprox to poison

This approximation is valid under specific conditions:

• When the number of trials, n, is very large (n → ∞).
• When the probability of success, p, is very small (p → 0).
• And the product np (which is the expected number of successes) is a finite, constant value, often denoted as λ.

In this case, the binomial distribution B(n, p) can be approximated by the Poisson distribution P(λ), where λ = np.

This approximation is useful for calculating probabilities of rare events occurring a certain number of times in a large number of trials.