Merge pull request #40 from juliohm/patch-2

Update README.md

Author: andreasnoack

README.md

@@ -27,6 +27,7 @@ This library provides the following functions:
  - `primorial(n)`: returns the product of all positive prime numbers <= n; always returns a `BigInt`;
  - `stirlings1(n, k, signed=false)`: returns the `(n,k)`-th Stirling number of the first kind; the number is signed if `signed` is true; returns a `BigInt` only if given a `BigInt`.
  - `stirlings2(n, k)`: returns the `(n,k)`-th Stirling number of the second kind; returns a `BigInt` only if given a `BigInt`.
+ - `nthperm(a, k)`: Compute the `k`th lexicographic permutation of the vector `a`.
 
 Young diagrams
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