bucku ubcku bcuku cbuku ucbku cubku bukcu ubkcu bkucu kbucu ukbcu kubcu bckuu cbkuu bkcuu kbcuu ckbuu kcbuu uckbu cukbu ukcbu kucbu ckubu kcubu bucuk ubcuk bcuuk cbuuk ucbuk cubuk buuck ubuck buuck ubuck uubck uubck bcuuk cbuuk bucuk ubcuk cubuk ucbuk ucubk cuubk uucbk uucbk cuubk ucubk bukuc ubkuc bkuuc kbuuc ukbuc kubuc buukc ubukc buukc ubukc uubkc uubkc bkuuc kbuuc bukuc ubkuc kubuc ukbuc ukubc kuubc uukbc uukbc kuubc ukubc bckuu cbkuu bkcuu kbcuu ckbuu kcbuu bcuku cbuku bucku ubcku cubku ucbku bkucu kbucu bukcu ubkcu kubcu ukbcu ckubu kcubu cukbu uckbu kucbu ukcbu uckub cukub ukcub kucub ckuub kcuub ucukb cuukb uuckb uuckb cuukb ucukb ukucb kuucb uukcb uukcb kuucb ukucb ckuub kcuub cukub uckub kucub ukcub
Note: these 'words' (valid or invalid) are all the permutations of the word bucku. These words are obtained by scrambling the letters in bucku.