! Copyright (c) 2008 Eric Mertens.
! See http://factorcode.org/license.txt for BSD license.
-USING: fry kernel math math.primes.factors math.vectors sequences sets
+USING: kernel math math.primes.factors math.vectors sequences sets
project-euler.common ;
IN: project-euler.203
[ 0 prefix ] [ 0 suffix ] bi v+ ;
: generate ( n -- seq )
- 1 - { 1 } [ (generate) ] iterate combine ;
+ 1 - { 1 } [ (generate) ] iterate union-all ;
: squarefree ( n -- ? )
factors all-unique? ;