Binomial probability & combinations

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For $X \sim \mathrm{Binomial}(n,p)$, this reports $C(n,k)$ and $P(X=k) = C(n,k)\, p^k (1-p)^{n-k}$. Probabilities use log-space evaluation for better numerical behavior when $n$ is moderate.

n (number of trials) k (number of successes) p (success probability)

What it computes. Exact combinatorial coefficient (when representable) and the PMF value at $k$.

Limitations. Independent Bernoulli trials assumed. Very large $n$ may still underflow to 0 in floating point. See the disclaimer.