banq abnq bnaq nbaq anbq nabq baqn abqn bqan qban aqbn qabn bnqa nbqa bqna qbna nqba qnba anqb naqb aqnb qanb nqab qnab
Note: these 'words' (valid or invalid) are all the permutations of the word banq. These words are obtained by scrambling the letters in banq.