rrun rrun rurn urrn rurn urrn rrnu rrnu rnru nrru rnru nrru runr urnr rnur nrur unrr nurr runr urnr rnur nrur unrr nurr
Note: these 'words' (valid or invalid) are all the permutations of the word rrun. These words are obtained by scrambling the letters in rrun.