rchb crhb rhcb hrcb chrb hcrb rcbh crbh rbch brch cbrh bcrh rhbc hrbc rbhc brhc hbrc bhrc chbr hcbr cbhr bchr hbcr bhcr
Note: these 'words' (valid or invalid) are all the permutations of the word rchb. These words are obtained by scrambling the letters in rchb.