nffas fnfas nffas fnfas ffnas ffnas nfafs fnafs naffs anffs fanfs afnfs nfafs fnafs naffs anffs fanfs afnfs ffans ffans fafns affns fafns affns nffsa fnfsa nffsa fnfsa ffnsa ffnsa nfsfa fnsfa nsffa snffa fsnfa sfnfa nfsfa fnsfa nsffa snffa fsnfa sfnfa ffsna ffsna fsfna sffna fsfna sffna nfasf fnasf nafsf anfsf fansf afnsf nfsaf fnsaf nsfaf snfaf fsnaf sfnaf nasff ansff nsaff snaff asnff sanff fasnf afsnf fsanf sfanf asfnf safnf nfasf fnasf nafsf anfsf fansf afnsf nfsaf fnsaf nsfaf snfaf fsnaf sfnaf nasff ansff nsaff snaff asnff sanff fasnf afsnf fsanf sfanf asfnf safnf ffasn ffasn fafsn affsn fafsn affsn ffsan ffsan fsfan sffan fsfan sffan fasfn afsfn fsafn sfafn asffn saffn fasfn afsfn fsafn sfafn asffn saffn
Note: these 'words' (valid or invalid) are all the permutations of the word nffas. These words are obtained by scrambling the letters in nffas.