binomial - nodef/extra-number GitHub Wiki
Find the number of ways to choose k elements from a set of n elements.
Similar: factorial, binomial, multinomial.
function binomial(n, k)
// n: elements in source set
// k: elements in choose set
const xnumber = require('extra-number');
xnumber.binomial(4, 1);
// → 4
xnumber.binomial(4, 2);
// → 6
xnumber.binomial(4, 3);
// → 4