# Binomial Coefficient

*Author: L. Grondin*

Number of ways to choose P objects among N. It's also the coefficient of the monome of degree P in the expansion of (1 + X)^N, thus the name.

N (N-P+1)*(N-P+2)*...*N

( ) = ∑ ------------------- P 1*2*...*P

# More

http://rosettacode.org/wiki/Evaluate_binomial_coefficients#Perl_6

# Notable features used

infix sub definition

reduction meta-operator

self-declared parameters

sequence operator to get a decreasing order

Zip metaoperator with list of different sizes

use of rational numbers as a default

Source code: binomial-coefficient.pl

use v6; sub infix:<choose> { [*] ($^n ... 0) Z/ 1 .. $^p } say 5 choose 3;