project-euler/Sidef/203 Squarefree Binomial Coefficients.sf

#!/usr/bin/ruby

# Author: Daniel "Trizen" Șuteu
# Date: 22 September 2016
# License: GPLv3
# Website: https://github.com/trizen

# https://projecteuler.net/problem=203

# Runtime: 0.142s

func pascal(rows) {
    var table = Hash()
    for n in (^rows) {
        table{(0..n -> map {|k| binomial(n, k) })...} = ()
    }
    table.keys.map {|n| Num(n) }.grep { .is_square_free }.sum
}

say pascal(51)